UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 10-K

Aon Corporation
(Exact Name of Registrant as Specified in its Charter)

        Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. YES ý    NO o

        Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.    o

        Indicate by check mark whether the registrant is an accelerated filer (as defined in Exchange Act Rule 12b-2) YES ý    NO o

        Aggregate market value of common stock held by non-affiliates of the registrant as of June 30, 2003 was $6,978,389,176.

        Number of shares of common stock outstanding as of February 27, 2004 was 314,719,764.

Documents incorporated by reference:

        Portions of Aon Corporation's Proxy Statement for the 2004 Annual Meeting of Stockholders to be held on May 21, 2004 are incorporated by reference in this Form 10-K in response to Part III, Items 10, 11, 12, 13 and 14.

PART I

Item 1.    Business

Overview

        Aon Corporation ("Aon"), through its various subsidiaries worldwide, serves its clients through three operating segments:

•

Risk and Insurance Brokerage Services acts as an advisor and insurance broker, which helps clients manage their risks, and negotiates and places insurance risk with insurance carriers through our global distribution network.



•

Consulting provides advice and services to clients for employee benefits, compensation, management consulting, communications and human resources outsourcing.



•

Insurance Underwriting provides specialty insurance products, including supplemental accident, health and life insurance; credit life, accident and health insurance; extended warranty products, and select property and casualty insurance products and services.

        Our clients include corporations and businesses, insurance companies, professional organizations, independent agents and brokers, governments, and other entities. We also serve individuals through personal lines, affinity groups, and certain specialty operations.

        Incorporated in 1979, Aon is the parent corporation of long-established and more recently formed companies. Today the company has approximately 54,000 employees in more than 125 countries and sovereignties.

Competition and Industry Position

(1)   Risk and Insurance Brokerage Services

        The Risk and Insurance Brokerage Services segment generated approximately 58% of our total operating segment revenues in 2003. This is the largest of our operating segments, with approximately 37,000 employees worldwide. Risk and insurance brokerage services are provided by certain indirect subsidiaries, including Aon Risk Services Companies, Inc.; Aon Holdings International bv; Aon Services Group, Inc.; Aon Re Worldwide, Inc.; Aon Limited (U.K.); and Cananwill, Inc.

        Our retail brokerage companies operate in a highly competitive industry and compete with a large number of retail insurance brokerage and agency firms, as well as individual brokers and agents and direct writers of insurance coverage. Specifically, this segment:

•

addresses the highly specialized product development and risk management needs of professional groups, insurance companies, service businesses, governments, healthcare providers, commercial organizations and non-profit groups, among others



•

provides affinity products for professional liability, life, disability income and personal lines for individuals, associations and businesses



•

provides wholesale brokerage, managing underwriting and premium finance services to independent agents and brokers as well as corporate clients



•

offers claims management and loss cost management services to insurance companies and firms with self-insurance programs



•

provides actuarial, loss prevention and administrative services to businesses and consumers.

        We measure our revenues in this segment under the following areas:

        Risk Management and Insurance Brokerage (Americas and International operations) encompasses our retail and wholesale brokerage services, affinity products, managing general underwriting, placement and captive management services, and premium finance services for small, mid-sized and large companies, including Fortune 500 corporations. The Americas' operations provide products and

services to clients in North and South America, the Caribbean and Bermuda. Our International risk operations offer similar products and services to the rest of the world. Risk management services also include risk identification and assessment, safety engineering, claims and loss cost management, and program administration.

        Retail brokerage has practice areas to deliver specialized advice and services in such segments as entertainment, media, financial institutions, marine, aviation, construction, healthcare and energy, among others.

        As a retail broker, Aon Risk Services generally serves as an advisor to corporate clients and can arrange a wide spectrum of risk management solutions, including property, general liability, professional and directors' and officers' liability, workers' compensation, and other exposures.

        Wholesale brokerage operations serve retail insurance brokers and independent agents in placing large and small accounts with both standard and specialty carriers. Our wholesale brokerage operations are a commercial resource for insurance products, specialty programs and exclusive facilities.

        In our managing general underwriting business, we provide outsourcing solutions to insurance companies, such as risk selection, premium rating, form design and client service, but we do not assume any underwriting risk.

        Aon's wholesale brokers and managing general underwriting units offer more than 450 insurance products and programs. Clients may access them directly, or through the Aon Specialty Product Network (ASPN), which we developed as a single-point-of-contact for agent and broker clients who need specialty insurance solutions for their customers.

        We are also a major provider in the management of captive insurance companies that enable our clients to manage risks that would be cost prohibitive or unavailable in traditional insurance markets.

        Reinsurance Brokerage and Related Services offers sophisticated advisory services in program design and claim recoveries that enhance the risk/return characteristics of insurance policy portfolios, improve capital utilization and evaluate and mitigate catastrophic loss exposures worldwide. An insurance or reinsurance company may seek reinsurance or other risk-transfer financing on all or a portion of the risks it insures. Brokerage services use dynamic financial analysis and capital market alternatives, such as transferring catastrophe risk through securitization.

        Aon Re Worldwide, Inc., its subsidiaries and its affiliates provide reinsurance services to insurance and reinsurance companies and other risk assumption entities by acting as brokers or intermediaries on all classes of reinsurance. While property and casualty lines dominate, our reinsurance activities also include specialty lines such as professional liability, medical malpractice, accident, life and health. Services include advice, placement of reinsurance and alternative risk transfer financing with capital markets, and related services such as actuarial, financial and regulatory consulting, portfolio analysis, catastrophe modeling, and claims services.

        Claim Services offers claims administration and loss cost management services through dedicated subsidiaries that are separate from our risk management and reinsurance brokerage services. In the United States, these services are delivered principally through Cambridge Integrated Services Group.

Compensation for Services

        Revenues are generated through commissions, fees from clients, and compensation from insurance and reinsurance companies with whom we place business for services provided to them. Commission rates and fees vary, depending upon several factors which may include the amount of premium, the type of insurance or reinsurance coverage provided, the particular services provided to an insurer or reinsurer, and the capacity in which the broker acts. We also receive investment income on funds held on behalf of clients.

3

Competitive Conditions

        We believe we are the second largest insurance broker worldwide based on total revenues. The risk and insurance brokerage services business is highly competitive and we compete with two other global brokers in addition to numerous specialist, regional and local firms in almost every area of our business; insurance and reinsurance companies that market and service their insurance products without the assistance of brokers or agents; and with other businesses, including commercial and investment banks, accounting firms and consultants that provide risk-related services and products.

(2)   Consulting

        The Consulting segment generated approximately 12% of our total operating segment revenues in 2003. It has approximately 7,500 employees worldwide located in more than 120 offices. We believe we are the world's third largest employee benefit consultant and the fifth largest in the United States based on total revenues.

        Through our Aon Consulting Worldwide, Inc. subsidiary, (Aon Consulting) we provide a full range of human capital management services in five practice areas:

1.

Employee Benefits advises clients regarding the structure, funding and administration of employee benefit programs, which attract, retain and motivate employees. Benefits consulting includes health and welfare, retirement, executive benefits, absence management, compliance, employee commitment, investment advisory and elective benefits services.



2.

Compensation focuses on designing salary, bonus, commission, stock option, and other pay structures, with special expertise in the financial services and technology industries.



3.

Management Consulting assists clients in process improvement and design; leadership, organization and human capital development; and change management.



4.

Communications advises clients on how to communicate initiatives that support their corporate vision.



5.

Human Resource Outsourcing offers employment processing, performance improvement, benefits administration, and other employment-related services.

        Aon Consulting works to maximize the value of clients' human resources spending, to boost employee productivity, and to improve employee performance. Its approach addresses a trend toward more diverse workforces (demographics, nationalities, cultures and work/lifestyle preferences) that require more choices and flexibility among employers—with benefit options suited to individual needs.

        Our consulting professionals and their clients also identify options in human resource outsourcing and process improvement. Prime areas where companies choose to use outsourcing services include the assessment and selection of job candidates, employment processing, training and development, benefits administration and the individual benefits enrollment process.

Compensation for Services

        Aon Consulting revenues are principally derived from fees paid by clients for advice and services. In addition, commission revenue is received from insurance companies for the placement of individual and group insurance contracts, primarily life, health and accident coverages.

Competitive Conditions

        Our consulting business faces strong competition from other privately and publicly held worldwide and national consulting companies, as well as regional and local firms. Competitors include independent consulting firms and consulting organizations affiliated with accounting, information

4

systems, technology and financial services firms. Some of our competitors provide administrative or consulting services as an adjunct to other primary services.

(3)   Insurance Underwriting

        Our insurance underwriting segment, with approximately 9,000 employees worldwide, has operations in the United States, Canada, Latin America, Europe and Asia/Pacific. This segment generated approximately 30% of Aon's total operating segment revenues in 2003. We classify our insurance underwriting businesses into two sub-segments: (1) accident & health and life, and (2) warranty, credit and property and casualty.

Accident & Health and Life

        Our Combined Insurance Company of America and Combined Life Insurance Company of New York (Combined) subsidiaries provide supplemental accident, health and life insurance. We are a leading underwriter and distributor of specialty individual accident, disability, health and life insurance products that are targeted to middle income consumers in the United States, Europe, Canada, Asia/Pacific and Latin America.

        A worldwide sales force of approximately 7,600 exclusive career agents service clients regularly to initiate and renew coverage and to sell additional coverage. We offer a wide range of accident and sickness insurance products, including short-term disability, cancer aid, Medicare supplement, disability income, and long-term care coverage. Most of these products are primarily fixed-indemnity obligations, and are not subject to escalating medical cost inflation.

        With the continuing rise of employee benefit costs, Combined also works with employers to contain those costs while offering quality benefits that appeal to their employees' individual needs. For example, a Worksite Solutions program complements existing benefits packages offered by employers with no additional cost to a company. Individual employees choose among supplemental insurance product options and pay for them through payroll deductions.

Compensation for Services

        Accident and health revenues are based on premiums paid by policyholders for insurance coverage and services.

Competitive Conditions

        The accident and health insurance industry in the United States is highly diverse, with more than 1,500 accident and health and life insurance companies competing in various segments of the industry. We believe that competition in our accident, health and life business is based on service, product features, price, commission structure, financial strength, claims-paying ability ratings, name recognition and new legislation or industry developments.

Warranty, Credit and Property and Casualty

        We believe we are the world's largest independent provider of extended warranty products. These products are offered through our Virginia Surety Company, Inc. and London General Insurance Company Limited subsidiaries.

        Extended warranty, which is the largest line of business in this sub-segment, offers extended service plans and warranties for:

•

some of the world's premier manufacturers, distributors and retailers of many types of consumer goods including automobiles, electronics, appliances, computers and telephone equipment

5

•

homebuyers and sellers.

        Services include compliance support, merchandising, direct marketing, training, and customer care management services. Products are sold through retailers, automotive dealers, insurance agents and brokers, and real estate brokers.

        Our credit life, accident and health, and disability insurance provides coverage for unpaid loans in the event of death, illness, accident or involuntary unemployment. This insurance is sold by automobile dealers with automobile financing, and by financial institutions with consumer loans. Other products include extended warranty or insurance protection for items purchased with a credit card and extended warranties on major home systems and appliances.

        Select property and casualty products are designed to protect businesses against losses related to various personal and commercial risks, such as professional liability errors and omissions, excess liability, and workers' compensation. We offer select commercial property and casualty business on a limited basis through managing general underwriters, primarily Aon-owned companies.

Compensation for Services

        Insurance revenues are based on premiums paid by policyholders. Certain other revenues are based on fees paid by clients for administrative and other services.

Competitive Conditions

        We believe that competition in our warranty, credit and specialty property and casualty business is based on service, product features, price, commission structure, financial strength, claims-paying ability, ratings and name recognition. In our extended warranty business, we compete with a large number of insurance companies and other financial services providers in addition to third-party administrators, manufacturers and distributors.

(4)   Discontinued Operations

        The Registrant hereby incorporates by reference a portion of note 1 "Automobile Finance Servicing Business" as well as note 6 "Discontinued Operations," of the Notes to Consolidated Financial Statements in Part II, Item 8 of this report.

Licensing and Regulation

        Regulatory authorities in the states or countries in which the operating subsidiaries of Aon Group conduct business may require individual or company licensing to act as brokers, agents, third party administrators, managing general agents, reinsurance intermediaries or adjusters. Under the laws of most states in the U.S. and of most foreign countries, regulatory authorities have relatively broad discretion with respect to granting, renewing and revoking brokers' and agents' licenses to transact business in the state or country. The manner of operating in particular states and countries may vary according to the licensing requirements of the particular state or country, which may require, among other things, that a firm operate in the state or country through a local corporation. In a few states and countries, licenses are issued only to individual residents or locally owned business entities. In such cases, Aon Group subsidiaries have arrangements with residents or business entities licensed to act in the state or country.

        Insurance companies must comply with laws and regulations of the jurisdictions in which they do business. These laws and regulations are designed to ensure financial solvency of insurance companies and to require fair and adequate service and treatment for policyholders. They are enforced by the states in the U.S., by the Financial Services Authority in the United Kingdom, and by various regulatory agencies in other countries through the granting and revoking of licenses to do business,

6

licensing of agents, monitoring of trade practices, policy form approval, minimum loss ratio requirements, limits on premium and commission rates, and minimum reserve and capital requirements. Compliance is monitored by the state insurance departments through periodic regulatory reporting procedures and periodic examinations. The quarterly and annual financial reports to the regulators in the U.S. utilize statutory accounting principles which are different from accounting principles generally accepted in the U.S. The statutory accounting principles, in keeping with the intent to assure the protection of policyholders are based, in general, on a liquidation concept, while accounting principles generally accepted in the U.S. are based on a going-concern concept.

        The state insurance regulators are members of the National Association of Insurance Commissioners ("NAIC"). The NAIC seeks to promote uniformity of, and to enhance the state regulation of, insurance. Both the NAIC and the individual states continue to focus on the solvency of insurance companies and their conduct in the marketplace. This focus is reflected in additional regulatory oversight by the states and emphasis on the enactment or adoption of a series of NAIC model laws and regulations designed to promote solvency. Effective January 1, 2001, the NAIC revised its Accounting Practices and Procedures Manual in a process referred to as Codification. The domiciliary states of Aon's major insurance subsidiaries have adopted the provisions of the revised manual. The revised manual has changed, to some extent, prescribed statutory accounting practices and resulted in changes to the accounting practices that Aon's major insurance subsidiaries use to prepare their statutory-basis financial statements.

        Several years ago, the NAIC developed a formula for analyzing insurers called risk-based capital ("RBC"). RBC is intended to establish "minimum" capital threshold levels that vary with the size and mix of a company's business. It is designed to identify companies with capital levels that may require regulatory attention.

        The state insurance holding company laws require prior notice to, and approval of, the domestic state insurance department of intracorporate transfers of assets within the holding company structure, including the payment of dividends by insurance company subsidiaries. In addition, the premium finance loans by Cananwill, an indirect wholly owned subsidiary of the Registrant, are subject to one or more truth-in-lending and credit regulations, insurance premium finance acts, retail installment sales acts and other similar consumer protection legislation. Failure to comply with such laws or regulations can result in the temporary suspension or permanent loss of the right to engage in business in a particular jurisdiction as well as other penalties.

        Recent federal and state laws and proposals mandating specific practices by medical insurers and the health care industry will not, because of the nature of the business of the Registrant's subsidiaries, materially affect the Registrant. Numerous states have had legislation introduced to reform the health care system, and such legislation has passed in several states. While it is impossible to forecast the precise nature of future federal and state health care changes, because most of the policies issued by the Registrant's insurance subsidiaries are supplemental in nature and provide, on a fixed-indemnity basis, protection against loss-of-time or disability benefits, the Registrant does not expect such legislation to have a material impact on its operations. Congress has passed the Financial Services Modernization Act, commonly known as S 900 or the Gramm-Leach-Bliley Act. While S 900 makes substantial changes in allowing financial organizations to diversify, the Registrant does not believe its enactment will have a material effect on the business of its insurance subsidiaries. The Health Insurance Portability and Accountability Act of 1996 (HIPAA) created a broad series of standards that the health insurance industry (as well as health care providers) is required to meet. Collectively, these various standards were designed to facilitate and promote the electronic exchange of health information. Because most of the policies issued by the Registrant's insurance subsidiaries are supplemental in nature and provide disability and other benefits on a fixed-indemnity basis, HIPAA has not had a material impact on the Registrant nor does the Registrant expect it to have any significant future impact on these operations.

7

        Beginning in January 2005, the Registrant's principle subsidiary in the U.K., Aon Limited, must be authorized by the Financial Services Authority ("FSA"). Currently, Aon Limited is a member of a self-regulatory body. Regulation by the FSA is being introduced pursuant to the European Insurance Mediation Directive, which sets minimum standards for those involved in advising on, arranging, administering or introducing contracts of insurance. The regulation requires significant operational changes, for example, enhanced disclosures, particularly in connection with retail (private and non-commercial) customers. The FSA has also indicated that it will adopt rules regarding use of client funds that will have significant consequences for all brokers operating in the London market.

Clientele

        No significant part of the Registrant's or its subsidiaries' business is dependent upon a single client or on a few clients, the loss of any one of which would have a material adverse effect on the Registrant or its operating segments.

Employees

        At December 31, 2003, the operating subsidiaries of the Registrant had approximately 54,000 employees, of whom approximately 50,000 are salaried and hourly employees and the remaining 4,000 are career agents who are generally compensated wholly or primarily by commission. In addition, there were approximately 3,600 international career agents who are considered independent contractors and are not employees of the Registrant. Of the total number of employees, 25,200 work in the U.S.

Risks Related to Our Business and the Insurance Industry

Our results may fluctuate as a result of many factors, including cyclical changes in the insurance and reinsurance industries.

        Our results historically have been subject to significant fluctuations arising from uncertainties in the insurance industry. Changes in premium rates affect not only the potential profitability of our underwriting businesses but also generally affect the commissions and fees payable to our brokerage businesses. In addition, insurance industry developments that can significantly affect our financial performance include factors such as:

•

rising levels of actual costs that are not known by companies at the time they price their products;



•

volatile and unpredictable developments, including weather-related and other natural and man-made catastrophes, including acts of terrorism;



•

changes in levels of capacity and demand, including reinsurance capacity; and



•

changes in reserves resulting from the general claims and legal environments as different types of claims arise and judicial interpretations relating to the scope of insurers' liabilities develop.

A decline in the credit ratings of our senior debt and commercial paper may adversely affect our borrowing costs and financial flexibility.

        In fourth quarter 2002, the credit rating agencies lowered the credit ratings of our senior debt and commercial paper. On October 31, 2002, Moody's Investors Service lowered its rating of our senior debt to the current rating of "Baa2" from "Baa1." Moody's also placed the rating of our senior debt and the "P-2" rating of our commercial paper under review for possible future downgrade, which it subsequently removed without change. Also on October 31, 2002, Standard & Poor's Ratings Services placed its "A-" rating of our senior debt on CreditWatch with negative implications, which it subsequently removed without change. On August 13, 2003, Standard & Poor's revised its outlook on

8

our senior debt from stable to negative. A further downgrade in the credit ratings of our senior debt and commercial paper would increase our borrowing costs and reduce our financial flexibility.

        Any such further downgrade may trigger a further obligation of our company to fund an aggregate of up to $75 million with respect to our premium finance securitizations. Moreover, some of our debt instruments, such as our 6.20% notes due January 2007 ($250 million of which are outstanding), expressly provide for interest rate increases in the case of certain ratings downgrades. Similarly, any such downgrade would increase our commercial paper interest rates or may result in our inability to access the commercial paper market altogether. If we cannot access the commercial paper market, although we have committed backup lines in excess of our currently outstanding commercial paper borrowings, we cannot assure you that it would not adversely affect our financial position. A downgrade in the credit ratings of our senior debt may also adversely affect the claims-paying ability or financial strength ratings of our insurance company subsidiaries. See "A decline in the financial strength or claims-paying ability ratings of our insurance underwriting subsidiaries may increase policy cancellations and negatively impact new sales of insurance products" below.

We face significant competitive pressures in each of our businesses.

        We believe that competition in our lines of business is based on service, product features, price, commission structure, financial strength, claims-paying ability ratings and name recognition. In particular, we compete with a large number of national, regional and local insurance companies and other financial services providers, brokers and, with respect to our extended warranty business, third-party administrators, manufacturers and distributors.

        Some of our underwriting competitors have penetrated more markets and offer a more extensive portfolio of products and services and have more competitive pricing than we do, which can adversely affect our ability to compete for business. Some underwriters also have higher claims-paying ability ratings and greater financial resources with which to compete and are subject to less government regulation than our underwriting operations.

        We encounter strong competition for both business and professional talent in our insurance brokerage and risk management services operations from other insurance brokerage firms which also operate on a nationwide or worldwide basis, from a large number of regional and local firms in the United States, the European Union and in other countries and regions, from insurance and reinsurance companies that market and service their insurance products without the assistance of brokers or agents, and from other businesses, including commercial and investment banks, accounting firms and consultants that provide risk-related services and products. Our consulting operations compete with independent consulting firms and consulting organizations affiliated with accounting, information systems, technology and financial services firms around the world.

        In addition, the increase in competition due to new legislative or industry developments could adversely affect us. These developments include:

•

an increase in capital-raising by insurance underwriting companies, which could result in new entrants to our markets and an influx of capital into the industry;



•

the selling of insurance by insurance companies directly to insureds;



•

the enactment of the Gramm-Leach-Bliley Act of 1999, which, among other things, permits financial institutions, such as banks and savings and loans, to sell insurance products, and also could result in new entrants to our markets;



•

the establishment of programs in which state-sponsored entities provide property insurance in catastrophe prone areas or other alternative markets types of coverage; and



•

changes in consumer buying practices caused by the Internet.

9

        New competition as a result of these developments could cause the supply of, and demand for, our products and services to change, which could adversely affect our results of operations and financial condition.

        A decline in the financial strength or claims-paying ability ratings of our insurance underwriting subsidiaries may increase policy cancellations and negatively impact new sales of insurance products.

        Claims-paying ability ratings are important factors in establishing the competitive position of insurance companies. These ratings are based upon criteria established by the rating agencies for the purpose of rendering an opinion as to an insurance company's financial strength, operating performance, strategic position and ability to meet its obligations to policyholders. They are not evaluations directed toward the protection of investors, nor are they recommendations to buy, sell or hold specific securities. Periodically, the rating agencies evaluate our insurance underwriting subsidiaries to confirm that they continue to meet the criteria of the ratings previously assigned to them. A downgrade, or the potential for a downgrade, of these ratings could, among other things, increase the number of policy cancellations, adversely affect relationships with brokers, retailers and other distributors of our products and services, negatively impact new sales and adversely affect our ability to compete.

        Virginia Surety Company, Inc., our principal property and casualty insurance company subsidiary, is currently rated "A" (excellent; third highest of 16 rating levels) by A.M. Best Company. Combined Insurance Company of America, the principal insurance subsidiary that underwrites our specialty accident and health insurance business, is currently rated "A" (excellent; third highest of 16 rating levels) by A.M. Best Company, "BBB+" (good; fourth highest of nine rating levels and highest ranking within the level) for financial strength by Standard and Poor's Ratings Services and "Baa1" (adequate; fourth highest of nine rating levels and highest ranking within the level) for financial strength by Moody's Investors Service. We cannot assure you that one or more of the rating agencies will not downgrade or withdraw their financial strength or claims-paying ability ratings in the future.

Changes in interest rates and investment prices could reduce the value of our investment portfolio and adversely affect our financial condition or results.

        Our insurance underwriting subsidiaries carry a substantial investment portfolio of fixed-maturity and equity and other long-term investments. As of December 31, 2003, our fixed-maturity investments (more than 96% of which were investment grade) had a carrying value of $2.8 billion, our equity investments had a carrying value of $42 million and our other long-term investments and limited partnerships had a carrying value of $716 million. Accordingly, changes in interest rates and investment prices could reduce the value of our investment portfolio and adversely affect our financial condition or results.

        For example, changes in domestic and international interest rates directly affect our income from, and the market value of, fixed-maturity investments. Similarly, general economic conditions, stock market conditions and other factors beyond our control affect the value of our equity investments. We monitor our portfolio for "other-than-temporary impairments" in carrying value. For securities judged to have an "other-than-temporary impairment," we recognize a realized loss through the statement of income to write down the value of those securities.

        For 2003, we recognized impairment losses of $36 million. We cannot assure you that we will not have to recognize additional impairment losses in the future, which would negatively affect our financial results.

        On December 31, 2001, our two major insurance companies sold the vast majority of their limited partnership portfolio, valued at $450 million, to Private Equity Partnership Structures I, LLC, (PEPS I) a qualifying special purpose entity (QSPE). We utilized this QSPE following the guidance contained in Financial Accounting Standards Board (FASB) Statement No. 140 (Statement No. 140) and other

10

relevant accounting guidance. The common stock interest in PEPS I is held by a limited liability company which is owned by one of our subsidiaries (49%) and by a charitable trust, which is not controlled by us, established for victims of the September 11 attacks (51%). Approximately $171 million of investment grade fixed-maturity securities were sold by PEPS I to unaffiliated third parties. PEPS I then paid our insurance underwriting companies the $171 million in cash and issued to them an additional $279 million in fixed-maturity and preferred stock securities. The fixed-maturity securities our insurance underwriting companies received from PEPS I are rated as investment grade by Standard & Poor's Ratings Services. As part of this transaction, our insurance underwriting companies are required to purchase from PEPS I additional fixed-maturity securities in an amount equal to the unfunded limited partnership commitments, as they are requested. As of December 31, 2003, these unfunded commitments amounted to $80 million. Based on the actions taken by the ratings agencies on October 31, 2002 for the parent company, credit support arrangements were put into place on January 27, 2003. If our insurance underwriting companies fail to purchase additional fixed-maturity securities as commitments are drawn down, we have guaranteed their purchase.

        Although the PEPS I transaction is expected to reduce the reported earnings volatility historically associated with directly owning limited partnership investments, it will not eliminate our risk of future losses. For instance, we must analyze our preferred stock and fixed-maturity interests in PEPS I for other-than-temporary impairment, based on the valuation of the limited partnership interests held by PEPS I, and recognize an impairment loss if necessary. We cannot assure you that we will not have to recognize impairment losses with respect to our PEPS I interests in the future.

        The FASB has a current project on its agenda that is expected to result in a change to accounting principles generally accepted in the United States with respect to financial asset transfers such as the PEPS I transaction. We cannot assure you that the current accounting for our PEPS I investments will be unaffected by these forthcoming changes.

Our pension liabilities may continue to grow, which could adversely affect our stockholders' equity, net income, cash flow and liquidity, and require us to make additional cash contributions to the pension plans.

        To the extent that the present value of the benefits incurred to date for pension obligations in the major countries in which we operate continue to exceed the market value of the assets supporting these obligations, our financial position and results of operations may be adversely affected. Primarily as a result of the decline in the equity markets over the past several years, some of our defined benefit pension plans, particularly in the U.K., have suffered significant valuation losses in the assets backing the related pension obligation.

        Current projections indicate that our 2004 defined benefit pension expense for our major pension plans would increase by approximately $40 million compared with 2003 and that cash contributions of approximately $195 million would be required in 2004, excluding any legislative relief being considered by the U.S. Congress. Total cash contributions to these major defined benefit pension plans in 2003 were $217 million, an increase of $141 million over 2002, and included $40 million originally anticipated and an early contribution of $100 million. Future estimates are based on certain assumptions, including discount rates, interest rates, fair value of assets for some of our plans and expected return on plan assets. Changes in our pension benefit obligations and the related net periodic costs or credits may occur in the future due to any variance of actual results from our assumptions and changes in the number of participating employees. As a result, there can be no assurance that we will not experience future decreases in stockholders' equity, net income, cash flow and liquidity or that we will not be required to make additional cash contributions in the future beyond those which have been announced.

We are subject to a number of contingencies and legal proceedings which, if determined unfavorably to us, would adversely affect our financial results.

11

        We are subject to numerous claims, tax assessments and lawsuits that arise in the ordinary course of business. The damages that may be claimed are substantial, including in many instances claims for punitive or extraordinary damages. The litigation naming us as a defendant ordinarily involves our activities as a broker, consultant, or provider of insurance products or as an employer. It is possible that, if the outcomes of these contingencies and legal proceedings were not favorable to us, it could materially adversely affect our future financial results. In addition, our results of operations, financial condition or liquidity may be adversely affected if in the future our insurance coverage proves to be inadequate or unavailable or there is an increase in liabilities for which we self-insure.

Our success depends, in part, on the efforts of our senior management and our ability to attract and retain experienced and qualified personnel.

        We believe that our continued success depends, in part, on the efforts of our senior management. The loss of the services of any of our executive officers for any reason could have a material adverse effect on our business, operating results and financial condition. In addition, our future success depends on our ability to attract and retain experienced underwriters, brokers and other professional personnel. Competition for such experienced professional personnel is intense. If we cannot hire and retain talented personnel, our business, operating results and financial condition could be adversely affected.

        We are subject to increasing costs arising from errors and omissions claims against us.

        We have experienced an increase in the frequency and severity of errors and omissions claims against us, which has and may continue to substantially increase our risk management expenses. In our insurance brokerage business, we often assist our clients with matters which include the placement of insurance coverage and the handling of related claims. Errors and omissions claims against us may allege our potential liability for all or part of the amounts in question. Errors and omissions claims could include, for example, the failure of our employees or sub-agents, whether negligently or intentionally, to place coverage correctly or notify claims on behalf of clients or to provide insurance carriers with complete and accurate information relating to the risks being insured. It is not always possible to prevent and detect errors and omissions, and the precautions we take may not be effective in all cases. In addition, errors and omissions claims may harm our reputation or divert management resources away from operating our business.

Our businesses are subject to extensive governmental regulation which could reduce our profitability or limit our growth.

        Our businesses are subject to extensive federal, state and foreign governmental regulation and supervision, which could reduce our profitability or limit our growth by increasing the costs of regulatory compliance, limiting or restricting the products or services we sell or the methods by which we sell our products and services or subjecting our businesses to the possibility of regulatory actions or proceedings. With respect to our insurance brokerage businesses, this supervision generally includes the licensing of insurance brokers and agents and third-party administrators and the regulation of the handling and investment of client funds held in a fiduciary capacity. Our continuing ability to provide insurance brokering and third-party administration in the jurisdictions in which we currently operate depends on our compliance with the rules and regulations promulgated from time to time by the regulatory authorities in each of these jurisdictions. Also, we can be affected indirectly by the governmental regulation and supervision of other insurance companies. For instance, if we are providing managing general underwriting services for an insurer we may have to contend with regulations affecting our client. Further, regulation affecting the insurance companies with whom our brokers place business can affect how we conduct those operations.

        Most insurance regulations are designed to protect the interests of policyholders rather than stockholders and other investors. In the United States, this system of regulation, generally administered by a department of insurance in each state in which we do business, affects the way we can conduct our

12

insurance underwriting business. Furthermore, state insurance departments conduct periodic examinations of the affairs of insurance companies and require the filing of annual and other reports relating to the financial condition of insurance companies, holding company issues and other matters.

        Although the federal government does not directly regulate the insurance business, federal legislation and administrative policies in several areas, including employee benefit plan regulation, age, race, disability and sex discrimination, investment company regulation, financial services regulation, securities laws and federal taxation, do affect the insurance industry generally and our insurance underwriting subsidiaries in particular. For example, federal financial services modernization legislation and privacy laws, such as HIPAA and the Gramm-Leach-Bliley Act, may result in additional regulatory compliance costs, limit the ability of our insurance underwriting subsidiaries to market their products or otherwise constrain the nature and scope of our operations. With respect to our international operations, we are subject to various regulations relating to, among other things, licensing, currency, policy language and terms, reserves and the amount of local investment. These various regulations also add to our cost of doing business through increased compliance expenses, the financial impact of use of capital restrictions and increased training and employee expenses. Furthermore, the loss of a license in a particular jurisdiction could restrict or eliminate our ability to conduct business in that jurisdiction.

        In all jurisdictions the applicable laws and regulations are subject to amendment or interpretation by regulatory authorities. Generally, such authorities are vested with relatively broad discretion to grant, renew and revoke licenses and approvals, and to implement regulations. Accordingly, we may be precluded or temporarily suspended from carrying on some or all of our activities or otherwise fined or penalized in a given jurisdiction. No assurances can be given that our businesses can continue to be conducted in any given jurisdiction as they have been in the past.

Our significant global operations expose us to various international risks that could adversely affect our business.

        A significant portion of our operations is conducted outside the United States. Accordingly, we are subject to legal, economic and market risks associated with operating in foreign countries, including:

•

the general economic and political conditions existing in those countries;



•

imposition of limitations on conversion of foreign currencies or remittance of dividends and other payments by foreign subsidiaries;



•

imposition or increase of withholding and other taxes on remittances and other payments by subsidiaries;



•

hyperinflation in certain foreign countries;



•

imposition or increase of investment and other restrictions by foreign governments;



•

differing business standards;



•

longer payment cycles;



•

greater difficulties in accounts receivables collection; and



•

the requirement of complying with a wide variety of foreign laws.

        Some of our foreign brokerage subsidiaries receive revenues in currencies that differ from their functional currencies. We must also translate the financial results of our foreign subsidiaries into United States dollars. Although we use various derivative financial instruments to help protect against adverse transaction and translation effects due to exchange rate fluctuations, we cannot eliminate such risks, and significant changes in exchange rates may adversely affect our results.

13

Our financial results could be adversely affected if assumptions used in establishing our underwriting reserves differ from actual experience.

        We maintain reserves as an estimate of our liability under insurance policies issued by our insurance underwriting subsidiaries. The reserves that we maintain that could cause variability in our financial results consist of (1) unearned premium reserves, (2) policy and contract claim reserves, and (3) future policy benefit reserves. Unearned premium reserves generally reflect our liability to return premiums we have collected under policies in the event of the lapse or cancellation of those policies. Under accounting principles generally accepted in the United States, premiums we have collected generally become "earned" over the life of a policy by means of a reduction in the amount of the unearned premium reserve associated with the policy. Unearned premium reserves are particularly significant with respect to our warranty business, given that the premiums we receive for warranty products generally cover an extended period of time. If there are significant lapses or cancellations of these types of policies, or expected losses for existing policies develop adversely and therefore premiums are not earned as expected, it may be necessary to accelerate the amortization of deferred policy acquisition expenses associated with the policies, because these deferred expenses are amortized over the projected life of the policies, or establish additional reserves to cover premium deficiencies.

        Policy and contract claim reserves reflect our estimated liability for unpaid claims and claims adjustment expenses, including legal and other fees and general expenses for administering the claims adjustment process, and for reported and unreported losses incurred as of the end of each accounting period. If the reserves originally established for future claims prove inadequate, we would be required to increase our liabilities, which could have an adverse effect on our business, results of operations and financial condition.

        The obligation for policy and contract claims does not represent an exact calculation of liability. Rather, reserves represent our best estimate of what we expect the ultimate settlement and administration of claims will cost. These estimates represent informed judgments based on our assessment of currently available data, as well as estimates of future trends in claims severity, frequency, judicial theories of liability and other factors. Many of these factors are not quantifiable in advance and both internal and external events, such as changes in claims handling procedures, inflation, judicial and legal developments and legislative changes, can cause our estimates to vary. The inherent uncertainty of estimating reserves is greater for certain types of liabilities, where the variables affecting these types of claims are subject to change and long periods of time may elapse before a definitive determination of liability is made. Reserve estimates are periodically refined as experience develops and further losses are reported and settled. Adjustments to reserves are reflected in the results of the periods in which such estimates are changed. Because setting the level of reserves for policy and contract claims is inherently uncertain, we cannot assure you that our current reserves will prove adequate in light of subsequent events.

        Future policy benefit reserves generally reflect our liability to provide future life insurance benefits and future accident, health insurance benefits on guaranteed renewable and non-cancelable policies. Future policy benefit reserves on accident, health and life products have been provided on the net level premium method. These reserves are calculated based on assumptions as to investment yield, mortality, morbidity and withdrawal rates that were determined at the date of issue and provide for possible adverse deviations.

The perceived conflicts associated with our insurance brokerage and underwriting businesses could limit our growth.

        Historically, we have not been able to fully exploit business opportunities due to the perceived conflicts associated with our insurance brokerage and underwriting businesses. For example, we have generally refrained from offering our extended warranty products and services through competing insurance brokers. Independent brokers have been reluctant to do business with our insurance

14

underwriting business because they believed that any fees or information provided to us would ultimately benefit our competing brokerage business. These brokers also have been concerned that any information gleaned by our underwriting business regarding their clients and their clients' insurance needs would be shared with our competing brokerage business to solicit new business from these clients. Similarly, competing underwriters have feared that our brokers could share information with our underwriting business in an effort to help secure desirable business or, alternatively, seek price quotes from them only for undesirable business. In the future, these perceived conflicts could limit our ability to expand our product and service offerings and seek new business through independent brokerage channels.

Each of our business lines may be adversely affected by an overall decline in economic activity.

        The demand for property and casualty insurance generally rises as the overall level of economic activity increases and generally falls as such activity decreases, affecting both the commissions and fees generated by our brokerage and consulting businesses and the premiums generated by our underwriting businesses. In particular, a growing number of insolvencies associated with an economic downturn, especially insolvencies in the insurance industry, could adversely affect our brokerage business through the loss of clients or by hampering our ability to place insurance and reinsurance business. Moreover, the results of our consulting business are generally affected by the level of business activity of our clients, which in turn is affected by the level of economic activity in the industries and markets these clients serve. As our clients become adversely affected by declining business conditions, they may choose to delay or forgo consulting engagements with us.

Recent and proposed accounting rule changes could negatively affect our financial position and results.

        Recent accounting changes effected and proposals made could negatively affect our financial position or results of operations. Under FASB Statement No. 142, which we adopted on January 1, 2002, goodwill is no longer being amortized, but must instead be tested annually for impairment in its value. Goodwill is the excess of cost over net assets purchased relating to business acquisitions. As of December 31, 2003, we had approximately $4.5 billion of goodwill on our balance sheet. If an impairment exists, we must recognize a non-cash charge equal to the impairment, thereby reducing our net worth. In 2003, we tested our goodwill and determined that there was no impairment. However, we cannot assure you that impairment will not exist when we perform testing in future periods, and any impairment charge we would be required to take would have a negative effect on our financial position and results. Under our principal credit facility that supports our commercial paper program, we are required to maintain a minimum net worth of $2.5 billion. As of December 31, 2003, our net worth calculated for this purpose was $4.5 billion.

We have substantial debt outstanding that could adversely affect our financial flexibility.

        We have substantial debt outstanding. As of December 31, 2003, we had total consolidated debt outstanding, including our redeemable preferred stock, of approximately $2.2 billion. This substantial amount of debt outstanding could adversely affect our financial flexibility.

We are a holding company and, therefore, may not be able to receive dividends in needed amounts from our subsidiaries.

        Our principal assets are the shares of capital stock of our subsidiaries, including our insurance underwriting companies. We have to rely on dividends from these subsidiaries to meet our obligations for paying principal and interest on outstanding debt obligations and for paying dividends to stockholders and corporate expenses. Payments from our underwriting subsidiaries are limited by governmental regulation and will depend on the surplus and future earnings of these subsidiaries. In some circumstances, specific payments from our insurance underwriting subsidiaries may require prior regulatory approval, and we may not be able to receive dividends from these subsidiaries at times and in the amounts we anticipate or require.

15

The volume of premiums we write and our profitability are affected by the availability of reinsurance and the size and adequacy of our insurance company subsidiaries' capital base.

        The level of business that our insurance underwriting subsidiaries are able to write depends on the size and adequacy of their capital base. Many state insurance laws to which they are subject impose risk-based capital requirements for purposes of regulating insurer solvency. Insurers having less statutory surplus than that required by the risk-based capital model formula generally are subject to varying degrees of regulatory scrutiny and intervention depending on the level of capital inadequacy. As of December 31, 2003, each of our insurance company subsidiaries has met the NAIC risk-based statutory surplus requirements.

        We purchase reinsurance for certain of the risks underwritten by our insurance company subsidiaries. Market conditions beyond our control determine the availability and cost of the reinsurance protection we purchase, which may affect the level of business we are able to write and our profitability. We cannot assure you that we will be able to maintain our current reinsurance facilities or that we can obtain other reinsurance facilities in adequate amounts and at favorable rates. If we are unable to renew our expiring facilities or to obtain new reinsurance facilities, either our net exposures would increase or, if we are unwilling to bear an increase in net exposures, we would have to reduce the level of our underwriting commitments. Either of these potential developments could adversely affect our underwriting business.

We cannot guarantee that our reinsurers will pay in a timely fashion, if at all.

        To better manage our portfolio of underwriting risk, we may, from time to time, purchase reinsurance by transferring part of the risk that we will assume (known as ceding) to a reinsurance company in exchange for part of the premium that we will receive in connection with the risk. Although reinsurance would make the reinsurer liable to us to the extent the risk were transferred (or ceded) to the reinsurer, it would not relieve us of our liability to our policyholders. Accordingly, we will bear credit risk with respect to our reinsurers, if any. Recently, due to industry and general economic conditions, there is an increasing risk of insolvency among reinsurance companies, resulting in a greater incidence of litigation and affecting the recoverability of claims. We cannot assure you that our reinsurers, if any, will pay the reinsurance recoverables owed to us or that they will pay these recoverables on a timely basis.

Information Concerning Forward-looking Statements

        This report contains certain statements relating to future results, which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from either historical or anticipated results, depending on a variety of factors. Potential factors that could impact results include the general economic conditions in different countries around the world, fluctuations in global equity and fixed income markets, exchange rates, rating agency actions, pension funding, ultimate paid claims may be different from actuarial estimates and actuarial estimates may change over time, changes in commercial property and casualty markets and commercial premium rates, the competitive environment, the actual costs of resolution of contingent liabilities and other loss contingencies, the heightened level of potential errors and omissions liability arising from placements of complex policies and sophisticated reinsurance arrangements in an insurance market in which insurer reserves are under pressure, and the timing and resolution of related insurance and reinsurance issues relating to the events of September 11, 2001.

Website Access to Reports and Other Information

        The Registrant's annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and all amendments to those reports are made available free of charge through the

16

Registrant's website (http://www.aon.com) as soon as practicable after such material is electronically filed with or furnished to the Securities and Exchange Commission. Also posted on the Registrant's website, and available in print upon request, are the charters for the Registrant's Audit Committee, Organization and Compensation Committee, Governance/Nominating Committee and Investment Committee, the Registrant's Governance Guidelines, the Registrant's Code of Ethics and the Registrant's Code of Ethics for Senior Financial Officers. Within the time period required by the SEC and the New York Stock Exchange, the Registrant will post on its website any amendment to or waiver of the Code of Ethics for Senior Financial Officers, as well as any amendment to the Code of Ethics or waiver thereto applicable to any executive officer or director. The information provided on our website is not part of this report, and is therefore not incorporated herein by reference.

Item 2.    Properties.

        The business activities of the Registrant and its subsidiaries are conducted principally in leased office space in cities throughout the world. Certain of the Registrant's subsidiaries do own and occupy office buildings in five states in the U.S. and certain foreign countries. In general, no difficulty is anticipated in negotiating renewals as leases expire or in finding other satisfactory space if the premises become unavailable. In certain circumstances, the Registrant or its subsidiaries may have unused space and may seek to sublet such space to third parties, depending upon the demands for office space in the locations involved.

Item 3.    Legal Proceedings.

        The Registrant hereby incorporates by reference note 15, "Contingencies," of the Notes to Consolidated Financial Statements in Part II, Item 8 of this report.

Item 4.    Submission of Matters to a Vote of Security Holders.

        None.

17

Executive Officers of the Registrant

        Executive officers of the Registrant are regularly elected by its Board of Directors at the annual meeting of the Board which is held following each annual meeting of the stockholders of the Registrant. With the exception of D. Cameron Findlay, who joined the Registrant on August 1, 2003, the executive officers of the Registrant were elected to their current positions on May 16, 2003 to serve until the meeting of the Board following the annual meeting of stockholders on May 21, 2004. Ages shown for executive officers are as of December 31, 2003.

        Information concerning Mr. Ryan and Mr. O'Halleran is incorporated by reference from the disclosure set forth under the heading "Election of Directors" in the Registrant's Proxy Statement for the 2004 Annual Meeting of Stockholders to be held on May 21, 2004.

18

PART II

Item 5.    Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Repurchases of Equity Securities.

        The Registrant's common stock, par value $1.00 per share, is traded on the New York Stock Exchange. The Registrant hereby incorporates by reference the "Dividends paid per share" and "Price range" data under the heading "Quarterly Financial Data" in Part II, Item 8 of this report.

        The Registrant had approximately 11,667 holders of record of its common stock as of February 27, 2004.

        The Registrant hereby incorporates by reference note 11, "Redeemable Preferred Stock, Capital Securities and Stockholders' Equity" of the Notes to Consolidated Financial Statements in Part II, Item 8 of this report.

        During the fourth quarter ended December 31, 2003, no purchases of the Registrant's common stock were made by or on behalf of the Registrant or any "affiliated purchaser" (as defined in Rule 10b-18(a)(3) under the Securities Exchange Act of 1934).

        Information relating to the compensation plans under which equity securities of the Registrant are authorized for issuance is set forth under Part III, Item 12 of this report and is incorporated herein by reference.

19

Item 6.    Selected Financial Data.

(1)

In first quarter 2002, Aon adopted FASB Statement No. 142, Goodwill and Other Intangible Assets, effective January 1, 2002. Beginning in 2002, amortization of goodwill is no longer included in net income. (See note 2 to the consolidated financial statements).

(2)

Adoption of SEC Staff Accounting Bulletin 101, effective January 1, 2000, net of tax.

20

Item 7.    Management's Discussion and Analysis of Financial Condition and Results of Operations.

        This Management's Discussion and Analysis is divided into six sections. First, an overview of the key drivers influencing our financial performance is provided by segment, along with an executive summary of 2003 financial results. Key recent events are then described that affected our financial results in 2003. Critical accounting policies and estimates are discussed, including certain accounting judgments important to understanding our financial statements. We then review our consolidated results and segments with year-to-year comparisons. Finally, we cover our financial condition and liquidity along with related disclosures as well as information on our off balance sheet arrangements.

        The outline for our Management's Discussion and Analysis is as follows:

21

OVERVIEW

Key Drivers of Financial Performance

        The key drivers of financial performance vary among our segments.

Segments

        Risk and Insurance Brokerage Services.    Brokerage segment results are affected by a number of key drivers, including (i) conditions in insurance markets generally (particularly fluctuations in premiums charged by insurance companies), (ii) success in attracting new clients and avoiding loss of existing clients, (iii) managing our expenses, (iv) fluctuations in foreign exchange rates and (v) interest income on our investments.

        When premium rates rise in a "hard market", commissions generally increase as well. However, when insurance costs rise, insurance buyers resist paying increased premiums that include higher commissions. The resistance often results in buyers:

•

raising their deductibles



•

reducing the limits and types of insurance coverage they purchase



•

switching to negotiated fees or commissions instead of straight commissions



•

entering the alternative insurance market (which can also increase our revenues because we offer these services).

        Consulting.    Consulting segment results are principally affected by (i) the employment levels of our clients that are mainly driven by economic conditions, (ii) governmental regulations affecting the health care market, employee benefit programs, and our clients' respective industries, (iii) success in attracting new clients and retaining existing clients, (iv) our success in cross selling services across business units, and (v) managing our overall level of expenses.

        Insurance Underwriting.    Underwriting segment revenues are affected by (i) consumer buying habits that are influenced by economic conditions, (ii) our assumption of select commercial property and casualty insurance business particularly from our managing underwriting group in our Risk and Insurance Brokerage Services segment, (iii) competition with other underwriters (including competition based upon claims-paying ratings), (iv) success in selling new policies, upselling existing policyholders and the persistency of these policies and (v) investment results. Investment income is derived primarily from our fixed maturity investments and some short-term investments. These investments approximate net policy liabilities. Segment expenses are mostly benefits to policyholders that include reserve adjustments, sales commissions to agents and fees to distributors.

        Corporate and Other.    The key driver of results in this segment has been investment income. For further information, see "Corporate and Other" in the Review by Segment section, below.

Liquidity

        Liquidity is derived from cash flows from our business, excluding funds held on behalf of clients, and from financing and is used for capital expenditures, to repay debt, to fund acquisitions and pension obligations and to pay dividends to our stockholders. Because we are a holding company, the receipt of dividend income from our subsidiaries may be affected by their ability to pay dividends (which, in the case of the insurance underwriting subsidiaries, is limited by regulatory and rating agency considerations). Tax considerations may affect access to cash generated from operations outside the United States, as can pension obligation decisions by trustees of international pension plans.

22

Executive Summary

        We are proud of the high quality of our services, the breath and depth of our intellectual capital and our product and service offerings, and the leading market positions that we have built. We believe our bottom line profitability, however, does not reflect the true potential of our organization. We are taking steps designed to improve margins that include:

•

Reviewing strategic alternatives for our non-core businesses, including the possible divestitures of our claims services businesses



•

Modifying our employee benefit programs



•

Leveraging our purchasing power with vendors, suppliers, and landlords



•

Prudently managing employee-related compensation and benefit expenses



•

Pursuing alternative resourcing strategies, such as outsourcing, to more efficiently provide non-client-facing services



•

Reviewing compensation arrangements with clients to improve the profitability of the valuable services we deliver



•

Offering additional services to existing clients who can benefit from our wide range of resources.

        In 2003, consolidated revenues grew 11% to $9.8 billion driven by solid demand for our services and products, along with the positive influence of foreign exchange rates. Furthermore,

•

Risk and Insurance Brokerage Services (previously called Insurance Brokerage and Other Services), our largest segment, exhibited good growth in most major business units.



•

Consulting revenues rose due to the full year impact of a large outsourcing contract, but were restrained by declining employment levels at many of our clients.



•

Our insurance underwriting business grew due to higher premiums within the warranty, credit and property & casualty lines.



•

Our accident, health and life lines are a lower growth business, and in 2003 revenue growth was constrained by the run-off of certain non-core businesses in Latin America, a large employer group life book in the U.S., and a specialty book in the U.K.



•

Our investment in Endurance Specialty stock and warrants increased our total investment income by $105 million over last year.

        Our pretax income from continuing operations and minority interest rose $286 million from 2002. Despite our Risk and Insurance Brokerage Services and Consulting margins declining, our overall pretax margin increased 190 basis points due to the increase in investment income from our investment in Endurance stock and warrants and the absence of $50 million of expenses in 2002 for the planned divestiture of our underwriting subsidiaries. We are, however, working to further improve our margins through greater financial discipline.

        Several factors that hurt our margins included:

•

increased defined benefit expenses for our major pension plans of $131 million



•

a significant decline in the pretax income of our claims services business of $48 million



•

increased adverse loss experience in a previously reported National Program Services, Inc. (NPS) run-off program of $29 million.

23

        We are doing a better job of generating and managing our cash. More specifically, we:

•

paid down more than $300 million of long-term debt in 2003. At year-end, our total level of debt and preferred stock outstanding was 33% of our total capitalization, which is down from 40% at the beginning of the year.



•

made an early $100 million pension plan contribution in 2003.



•

reduced capital expenditure spending, which was down 33% from 2002. We are targeting even lower capital expenditures in 2004 as our major investments in businesses, systems and facilities are now largely complete.



•

reduced the amount we spent on cash acquisitions by 50% compared with 2002.

        Further discussion of these items may be found in the remainder of this Management's Discussion and Analysis.

KEY RECENT EVENTS

Segment Reporting, Reclassification and Cost Reallocation

        We classify our businesses into three operating segments: Risk and Insurance Brokerage Services, Consulting, and Insurance Underwriting. A fourth segment, Corporate and Other, when added to the operating segments and after eliminating intersegment revenues, totals to the amounts included in our consolidated financial statements.

        In 2003, certain business units were reclassified among segments. Certain administrative and marketing services relating to our insurance underwriting operations, previously included in the Risk and Insurance Brokerage Services segment, were reclassified into the Insurance Underwriting segment. Our automotive finance servicing business, previously included in the Risk and Insurance Brokerage segment, was sold in fourth quarter 2003. Activity attributable to this business has been reflected in discontinued operations in the consolidated statements of income.

        Certain amounts in prior years' consolidated financial statements relating to segments and discontinued operations have been reclassified to conform to the 2003 presentation.

        Also, beginning in 2003, we refined our methodology for allocating certain costs to the segments. For 2003, this revised cost allocation methodology reduced Consulting and Insurance Underwriting segment pretax income by approximately $16 million and $12 million, respectively, with the $28 million offset reflected in the Risk and Insurance Brokerage Services segment. The revised methodology improves the assignment of costs, which are controlled on a centralized basis, to the operating segments.

Run-off and Discontinuance of Certain Operations

        We are pursuing a "back to basics" strategy in the accident and health insurance business, and focusing on core products and regions. Therefore, in February 2003, we announced that we would be placing in run-off our accident and health insurance underwriting operations in Mexico, Argentina and Brazil. In addition, we transferred to a third party our U.S. large employer group life and accidental death insurance business via an indemnity reinsurance arrangement. These lines of business generated approximately $14 million of revenues and $6 million of pretax losses in 2003, compared to $94 million of revenues and $22 million of pretax losses in 2002.

        In the United Kingdom in 2003, we decided to run-off certain non-core special risk accident and health business. This business generated $36 million of revenue with pretax income of $4 million in 2003. For 2002, we earned revenues of $37 million, generating pretax income of approximately $6 million.

24

        In third quarter 2003, we decided to sell our automotive finance servicing business, which has been in run-off since first quarter 2001, and completed the sale in fourth quarter 2003 for net proceeds of approximately $18 million. Operating results from prior periods attributable to this unit have been reclassified as discontinued operations. Revenues from this business were $13 million in 2003 versus $15 million in 2002. The pretax loss recorded in 2003 of $55 million is comprised of operating losses of $32 million and a loss from the revaluation of the business of $23 million. In 2002, our pretax loss was $31 million. (See note 1 to the consolidated financial statements for more information about this discontinued operation).

        We are evaluating options within our portfolio of other non-core businesses. In 2003, we announced that we were evaluating various strategic options for our claims services group. In early 2004, we reached an agreement in principle for the sale of two pieces of our claims services business in the U.K., and we are examining opportunities for the remaining claims units.

World Trade Center

        To resume business operations and minimize the loss caused by the World Trade Center disaster, we secured temporary office space in Manhattan. Subsequently, we leased permanent space, and during first quarter 2003, we assigned this temporary space to another company. The 2003 costs relating to this assignment were $46 million pretax.

        In November 2003, we reached a final settlement of approximately $200 million for our overall World Trade Center property insurance claim and received a final cash payment of $92 million ($108 million received previously). This settlement resulted in a pretax gain of $60 million. This gain, and the $46 million expense discussed above, were combined and reported as a $14 million Unusual credit-World Trade Center in the 2003 consolidated statements of income.

Endurance Warrants and Common Stock Investment

        In December 2001, Aon, primarily through its underwriting subsidiaries, invested $227 million in Endurance Specialty Holdings, Ltd., formerly known as Endurance Specialty Insurance Ltd. (Endurance), a Bermuda-based insurance and reinsurance company formed to provide additional underwriting capacity to commercial property and casualty insurance and reinsurance clients. As of December 31, 2003, the carrying value of our common stock investment in Endurance was $298 million, representing approximately 11.3 million shares.

        In conjunction with this common stock investment, we received approximately 4 million stock warrants, which allow us to purchase additional Endurance common stock through December 2011. These warrants meet the definition of a derivative as described in FASB Statement No. 133, Accounting for Derivative Instruments and Hedging Activities, which requires them to be recorded in the financial statements at fair value, with changes in fair value recognized in earnings each quarter.

        Through December 31, 2002, these warrants had been carried at zero value, which approximated their original cost. In first quarter 2003, Endurance completed its initial public offering, which provided a market value for the underlying shares and removed much of the uncertainty regarding the fair value of Endurance and the warrants. At December 31, 2003, we determined that the warrants had a fair value of approximately $80 million.

        This increase in value was recognized in investment income in the Corporate and Other segment. The future value of the warrants may vary considerably from the value at December 31, 2003 given the inherent volatility of the underlying shares, as well as the passage of time, and changes in other factors used in the valuation model. (See note 1 to the consolidated financial statements for additional information related to the valuation of the warrants.)

25

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

        Aon's consolidated financial statements have been prepared according to accounting principles generally accepted in the United States (GAAP). To prepare these financial statements, we made estimates, assumptions, and judgments that affect:

•

what we report as our assets and liabilities



•

what we disclose as contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the periods presented.

        In accordance with our policies, we:

•

regularly evaluate our estimates, assumptions and judgments, including those concerning revenue recognition, investments, intangible assets, income taxes, financing operations, policy liabilities (including future policy benefit reserves, unearned premium reserves and policy and contract claim reserves), restructuring costs, retirement benefits, and contingencies and litigation.



•

base our estimates, assumptions, and judgments on our historical experience and on factors we believe reasonable under the circumstances.

        The results allow us to make judgments about the carrying values of assets and liabilities not readily apparent from other sources. If our assumptions or conditions change, the actual results we report may differ from these estimates.

        We believe the following critical accounting policies, among others, affect the more significant estimates, assumptions and judgments we used to prepare these consolidated financial statements.

Pensions

U.S. Plans

        Effective January 1, 2004, the U.S. pension plans were closed to new entrants. All new employees will participate in a defined contribution plan. Over time, this change will reduce the volatility inherent in the accounting for the U.S. pension plans.

        Aon uses a market-related value of assets to calculate pension expense. This value reflects a five-year average of the difference between the expected return on the market-related value of plan assets and the actual market value return. The prior year market-related value is projected to the current date by adjusting for contributions, benefit payments and expected returns. The asset gain or loss is the difference between the expected return on assets and the actual return on assets. Twenty percent of the asset gain or loss is recognized in the current year's market-related value, with the remaining eighty percent spread evenly over the next four years. As of year-end 2003, accumulated asset losses of $185 million have not yet been reflected in the market-related value of assets. These losses will increase pension expense as they are graded into the market-related asset value and may be offset by future asset gains. As of year-end 2003, we reported a fair value of pension assets of $929 million. At the same point in time, the market-related value of assets is $1,114 million.

        Under FASB Statement No. 87 accounting, the full gain or loss on assets and obligations are not recorded as expense in the current period. Statement No. 87 allows changes in the projected benefit obligation and market value of assets to be deferred and amortized as a component of pension expense over several years, based on the average expected future service of active employees, which is currently nine years. Gains and losses on pension obligations include the net effects of changes in the discount rate as well as demographic changes in the employee data. For the 2003 valuation year, the pension plans have a combined deferred loss of $496 million (comprised of unrecognized asset losses of $185 million and other than deferred asset losses of $311 million) that has not yet been recognized through income in the financial statements. Only the other than deferred asset losses of $311 million

26

outside of a corridor, defined as 10% of the greater of the market related value of plan assets or the projected benefit obligation, is subject to amortization over a nine year period. For 2004, the estimated amortization amount to be recognized in expense is $23 million. To the extent not offset by future gains, the incremental amortization as calculated above will continue to affect future pension expense in a similar manner until fully amortized.

        The investment policy for the pension plan provides for an allocation of assets to various asset classes. According to the policy, the percentage of total assets invested in each class should fall within a range. There is a target allocation for long-term investment decisions. However, the range provides flexibility to accommodate prevailing market conditions. In order to determine the expected long-term rate of return for the pension plan, the historical performance, investment community forecasts and current market conditions are analyzed to develop expected returns for each of the asset classes used by the plan. In setting the individual asset assumptions, the historical performance data series were weighted most heavily toward the geometric average returns. The expected returns for each asset class were then weighted by the target allocation of the plan. The expected long-term rate of return assumption used to determine pension expense was 8.5%.

        The result of the calculation based on the actual asset allocation for year-end 2003 is shown in the following table. The actual return for the 2003 valuation year (12%) was well in excess of the assumed return.

        There are several assumptions that impact the actuarial calculation of pension obligations and, in turn, net periodic pension expense in accordance with Statement No. 87. These assumptions require various degrees of judgment. The most significant assumptions are (1) the expected return on plan assets and (2) the discount rate. The same assumptions are used for Aon's pension plans and postretirement benefit plans. Changes in these assumptions can have a material impact on pension obligations and pension expense. For example, holding all other assumptions constant, a one percentage point decrease in our estimated discount rate would increase the estimated 2004 pension expense and the estimated 2004 postretirement medical benefit expense by approximately $32 million and $1 million, respectively. A one percentage point increase in the estimated discount rate would decrease the estimated pension expense and the postretirement medical benefit expense for 2004 by approximately $28 million and $1 million, respectively.

        Similarly, holding other assumptions constant, a one percentage point decrease in Aon's estimated long-term rate of return on plan assets would increase the pension expense for the year ended December 31, 2004 by approximately $11 million. A one percentage point increase in the estimated long-term rate of return would decrease pension expense by approximately $11 million for the same period.

27

        Required cash contributions are also sensitive to assumptions, but assumptions used to determine contributions to the plan are changed infrequently. Under current rules and assumptions, we anticipate cash funding requirements of $28 million in 2004 and $236 million in 2005. Legislation being considered in Congress will relieve some of these requirements if passed. If so, contribution requirements are estimated to be $3 million in 2004 and $128 million in 2005.

Major U.K. Plans

        For purposes of determining pension expense, the fair market value of plan assets is used. During 1999, the U.K. pension plans were closed to new entrants. All new employees became participants in a defined contribution plan. As with the U.S. plan, it is anticipated that this change will, over time, reduce the volatility of the accounting for U.K. pension plans. As with our other international plans, it is also important to note that the U.K. plans are solely obligations of subsidiaries of Aon Corporation.

        For the 2003 valuation year, the major U.K. pension plans have a combined deferred loss (from asset and liability experience) of $1,404 million that has not yet been recognized through income in the financial statements. Only the accumulated loss outside of a corridor, defined as 10% of the greater of the fair value of plan assets or the projected benefit obligation, is subject to amortization over a period of approximately 17 years. For 2004, the estimated amortization amount to be recognized in expense is $63 million. To the extent not offset by future gains, the incremental amortization as calculated above will continue to affect future pension expense in a similar manner until fully amortized.

        Generally, the trustees of the U.K. plans determine the investment policy for each plan. In the aggregate, at the end of 2003 the plans were invested 65% in equities and 35% in fixed income securities. In determining the expected rate of return, the redemption yields available on the type of fixed income securities (corporate and U.K. government securities) used in the pension plans are reviewed. For equity returns, the expectations of the investment managers for the next 10 to 15 years are considered taking into account projected rates of future inflation and real returns. The expected long-term rate of return assumption was 7.5%.

        With respect to U.K. pension liabilities, a one percentage point decrease in the Company's estimated discount rate would increase the estimated 2004 U.K. pension expense by approximately $56 million. A one percentage point increase in the estimated discount rate would decrease the U.K. pension expense for 2004 by approximately $49 million.

        Similarly, a one percentage point decrease in the Company's estimated long-term rate of return on plan assets would increase the U.K. pension expense for the year ending December 31, 2004 by approximately $20 million. A one percentage point increase in the estimated long-term rate of return would decrease pension expense by approximately $20 million for the same period.

        Cash flow requirements are also sensitive to assumptions, but assumptions used for funding the U.K. plans are changed infrequently. Under current rules and assumptions, we anticipate U.K. funding requirements of $144 million in 2004 and $185 million in 2005. Such contributions reflect minimum funding requirements plus such other amounts agreed to with the trustees of the U.K. plans.

Dutch Plan

        For purposes of determining pension expense, the fair market value of plan assets is used. At the end of 2003, the Dutch pension plan has a combined deferred loss of $125 million that has not yet been recognized through income in the financial statements. Only the accumulated loss outside of a corridor, defined as 10% of the greater of the fair value of plan assets or the projected benefit obligation, is subject to amortization over a period of approximately 20 years. For 2004, the estimated amortization amount to be recognized in expense is $5 million. To the extent not offset by future gains,

28

the incremental amortization as calculated above will continue to affect future pension expense in a similar manner until fully amortized.

        The target asset allocation is 35% equities and 65% in fixed income securities, with an allowed deviation of 5%. At year-end 2003, the actual asset allocation was 38% equities and 62% fixed income. The expected long-term rate of return assumption is 6%, which results from an expected future return of 8% on equities and a 5% return on fixed income investments.

        With respect to Dutch pension liabilities, a 25 basis point decrease in the Company's estimated discount rate would increase the estimated 2004 Dutch pension expense by approximately $2 million. A 25 basis point increase in the estimated discount rate would decrease the estimated Dutch pension expense for 2004 by approximately $2 million.

        A one percentage point decrease in the Company's estimated long-term rate of return on plan assets would increase the pension expense for the year ending December 31, 2004 by approximately $3 million, while a one percentage point increase in the estimated long-term rate of return would decrease pension expense by approximately $3 million for the same period.

        At year-end 2003, the Dutch pension plan had a prepaid pension asset of $88 million. In the future, should the funded status of the plan deteriorate, such an amount could be reflected in a minimum pension liability, thereby reducing stockholders' equity.

Contingencies

        We define as a contingency any material condition that involves a degree of uncertainty that will ultimately be resolved. Under GAAP, we are required to establish reserves for contingencies when a loss is probable and we can reasonably estimate its financial impact.

        We are required to assess the likelihood of material adverse judgments or outcomes as well as potential ranges or probability of losses. We determine the amount of reserves required, if any, for contingencies after carefully analyzing each individual issue. The required reserves may change due to new developments in each matter, or changes in approach, such as a change in settlement strategy in dealing with these matters.

Policy Liabilities

        Through our insurance underwriting operations, we collect premiums from policyholders, and we establish liabilities (reserves) to pay benefits to policyholders. The liability for policy benefits, claims, and unearned premiums are some of the largest liabilities included in our statements of financial position. This liability is comprised primarily of estimated future payments to policyholders, policy and contract claims, and unearned and advance premiums and contract fees.

        To establish policy liabilities, we rely upon estimates for reported and anticipated claims, our historical experience, other actuarial data and, with respect to accident, health and life liabilities, assumptions on investment yields. We base interest rate assumptions on factors such as market conditions and expected investment returns. Although mortality and interest rate assumptions are locked-in when we issue new insurance policies, we may need to provide for expected losses on a product by reducing previously capitalized acquisition costs established for that product, or by establishing premium deficiency reserves if there are significant changes in our experience or assumptions. The process of estimating and establishing policy and contract liabilities is inherently uncertain and the actual ultimate cost of a claim may vary materially from the estimated amount reserved.

        While we made every effort to estimate these liabilities effectively, the results we report in our consolidated financial statements could be affected by trends which do not match historical experience

29

or which differ from our underlying assumptions. Furthermore, when our actual experience differs from our previous estimate, the difference will be reflected in the results we report for the period when we changed our estimate. We always consider trends in actual experience as a significant factor in helping us determine claim reserve levels.

Intangible Assets

        Intangible assets represent the excess of cost over the value of net tangible assets of acquired businesses. We classify our intangible assets as either goodwill, client lists, non-compete agreements, future profits of purchased books of business of the insurance underwriting subsidiaries, or other purchased intangibles. Intangible assets other than goodwill are amortized using the straight-line method over their estimated useful lives, while goodwill is not subject to amortization. Allocation of intangible assets between goodwill and other intangible assets and the determination of estimated useful lives are based on valuations we perform internally or that we receive from qualified independent appraisers. The calculations of these amounts are based on estimates and assumptions using historical and pro forma data and recognized valuation methods. The use of different estimates or assumptions could produce different results. Intangible assets are carried at cost, less accumulated amortization in the accompanying consolidated statements of financial position.

        While goodwill is not amortized, it is subject to periodic reviews for impairment (at least annually or more frequently if impairment indicators arise). We review goodwill for impairment periodically and whenever events or changes in business circumstances indicate that carrying value of the assets may not be recoverable. Such impairment reviews are performed at the reporting unit level with respect to goodwill. Under those circumstances, if the fair value were less than the carrying amount of the reporting unit, an indicator of impairment would exist and further analysis would be required to determine whether or not a loss would need to be charged against current period earnings. No such indicators were noted in 2003 and 2002. The determinations of impairment indicators and fair value are based on estimates and assumptions related to the amount and timing of future cash flows and future interest rates. The use of different estimates or assumptions could produce different results.

30

REVIEW OF CONSOLIDATED RESULTS

General

        In the discussion of operating results, we sometimes refer to supplemental information extracted from consolidated financial information which is not required to be presented in the financial statements by U.S. GAAP.

        Supplemental information related to organic revenue growth is information that management believes is an important measure to evaluate business production from existing operations. We also believe that this supplemental information is helpful to investors. Organic revenue growth excludes from reported revenues the impact of foreign exchange, acquisitions, divestitures, transfers between business units, investment income, reimbursable expenses, unusual items, and for the underwriting segment only, an adjustment between written and earned premium.

        The supplemental organic revenue growth information does not affect net income or any other GAAP reported figures. It should be viewed in addition to, not in lieu of, our consolidated statements of income. Industry peers provide similar supplemental information about their revenue performance, although they do not make identical adjustments.

        Aon has offices in more than 125 countries and sovereignties. Movement of foreign exchange rates in comparison to the U.S. dollar may be significant and may distort true period-to-period comparisons of changes in revenue or pretax income. Therefore, management has isolated the impact of the change in currencies between periods by providing percentage changes on a comparable currency basis for revenue, and has disclosed the effect on earnings per share. Reporting on this basis gives financial statement users more meaningful information about our operations.

        Certain tables in the segment discussions show a reconciliation of organic revenue growth percentages to the reported revenue growth percentages for the segments and sub-segments. We separately disclose the impact of foreign currency as well as the impact from acquisitions, divestitures, and transfers of business units, which represent the most significant reconciling items. Other reconciling items are generally not significant individually, or in the aggregate, and are therefore totaled in an "all other" category. If there is a significant individual reconciling item within the "all other" category, we provide additional disclosure in a footnote.

31

Summary Results for 2001 through 2003

        The consolidated results of continuing operations follow:

Consolidated Results for 2003 Compared to 2002

Revenue

        In 2003, revenue increased 11% over 2002 to $9.8 billion. We saw improvements in brokerage commissions and fees, premiums earned, and investment income. Excluding the effect of foreign exchange rates, revenue increased 6%. We do not directly hedge revenues against foreign currency translation because it is not cost effective, but we do attempt to mitigate the effect of foreign currency fluctuations on pretax income through hedging strategies.

        Consolidated revenue by geographic area follows:

        U.S. consolidated revenue, which represents 53% of total revenue, increased 4% in 2003 compared to 2002, as a result of growth driven:

•

primarily by new business development and improved retention rates in both retail and reinsurance brokerage.



•

secondarily by revenue gains in the Consulting segment as the result of a large outsourcing contract that began in third quarter 2002. These gains were partially offset by a decrease in revenue in our Accident & Health and Life sub-segment that was primarily from transferring our

32

U.S. large employer group life and accidental death business to a third party via an indemnity reinsurance arrangement.

        While moderating, commercial property and casualty premium rate increases for most lines of coverage continued in 2003. As a broker, we benefit from this through increased commissions. In addition, client demand for risk retention programs and services contributed to this increase, especially reinsurance and wholesale brokerage.

        U.K. and Continent of Europe revenue combined increased 21% to $3.3 billion and Rest of World revenue increased 23%, reflecting a positive impact from foreign exchange, strong new business, and increasing premium and retention rates.

        Brokerage commissions and fees increased 11% to $6.9 billion as a result of:

•

the growth in new business



•

improved renewal rates for most of our businesses



•

the weakening U.S. dollar



•

higher revenue from a large consulting segment outsourcing contract begun in third quarter 2002.

        Premiums and other, primarily related to insurance underwriting operations, improved to $2.6 billion, a 10% increase over 2002. The increase reflects growth in some warranty and credit programs, along with specialty property and casualty lines, and favorable foreign exchange rates.

        Investment income increased by 26% over 2002, and includes related expenses and income or loss on disposals and impairments. The net increase reflects:

•

lower impairment write-downs in 2003 of $36 million compared with $130 million last year. 2002 impairment write-downs included a $51 million cumulative adjustment related to prior reporting periods.



•

a non-cash increase in the value of Endurance stock warrants of $80 million and equity earnings from our investment in Endurance common stock of $46 million. Equity earnings from our Endurance investment in 2002 were $21 million.



•

investment income in 2002 included interest on a tax-related settlement of $48 million with no corresponding amount in 2003.



•

lower investment income generated by the operating units of $81 million, including $27 million on deposit-type contracts, reflecting lower rates.

Expenses

        Total expenses increased $717 million or 9% over 2002.

        General expenses increased 10% over 2002, reflecting:

•

growth of the businesses



•

the effect of foreign exchange rates



•

higher overall defined benefit pension plan costs of $131 million for our major plans.

        General expenses in 2002 included $50 million of costs from the planned divestiture of the insurance underwriting segment and a credit of $6 million reflecting the reversal of termination benefits previously incurred as part of the business transformation plan.

33

        Benefits to policyholders rose $52 million, or 4%, primarily as the result of new business volume, and losses and reserve strengthening of $65 million related to NPS, a non-core book of runoff business. NPS was hired to handle quoting, binding, premium collection, claims adjusting, and other servicing related to general liability insurance policies issued by one of Aon's subsidiaries. We stopped NPS from initiating any new business on our behalf in mid-2002 after we obtained a temporary restraining order. We and others sued NPS for fraud, among other things.

        Benefit payout ratios have declined, however, due to a shift in product mix.

        Interest expense was down primarily due to lower debt levels. Amortization of intangible assets grew $9 million from 2002 due primarily to the impact of recent acquisitions as well as foreign exchange rates in the risk and insurance brokerage services segment.

        Total expenses also included a $14 million credit in 2003 and a $29 million credit in 2002 related to the World Trade Center. The 2003 credit represents a $60 million gain from a final settlement of our World Trade Center property insurance claim, net of $46 million related to the assignment to a third party of temporary office space secured in Manhattan after the World Trade Center was destroyed. The 2002 credit represents a gain resulting from a settlement with our insurance carriers regarding reimbursement for depreciable assets destroyed.

Income from Continuing Operations Before Income Tax and Minority Interest

        Income from continuing operations before income tax and minority interest increased $286 million in 2003 to $1.1 billion. Contributing to this increase were the impact of foreign exchange, the improvement in investment income ($65 million) and 2002 expenses related to the planned spin-off ($50 million) with no corresponding amount in 2003. Approximately 67% of Aon's 2003 consolidated income from continuing operations before income tax and minority interest was from international operations.

Income Taxes

        The effective tax rate was 37% in both 2003 and 2002. The overall effective tax rate is higher than the U.S. federal statutory rate primarily because of state income taxes.

Income from Continuing Operations

        Income from continuing operations increased to $663 million ($2.08 per dilutive share) from $486 million ($1.71 per dilutive share) in 2002. Basic income from continuing operations per share was $2.08 and $1.72 for 2003 and 2002, respectively. In the fourth quarter 2002, we had a common stock offering, which increased the number of average common and common stock equivalent shares outstanding. After netting the effect of currency hedges, the positive impact of foreign currency translations was approximately $0.13 per share. We have deducted dividends paid for the redeemable preferred stock from net income to compute income per share.

Discontinued Operations

        After-tax losses from our discontinued automotive finance servicing business in 2003 were $35 million ($0.11 per both basic and dilutive share). In comparison, losses in 2002 from this discontinued operation were $20 million ($0.07 per both basic and dilutive share). The 2003 results include an after-tax loss on the revaluation of the automotive finance servicing business of $14 million.

        Discontinued operations also include certain insurance underwriting subsidiaries acquired with Alexander and Alexander Services, Inc. (A&A) that are in run-off and the indemnification by A&A of certain liabilities relating to subsidiaries sold by A&A before its acquisition by Aon. There was no income statement impact from these discontinued operations in 2003, 2002 or 2001.

34

        Based on current estimates, management believes that these discontinued operations are adequately reserved. The net liability is included as a component of other liabilities on the consolidated statements of financial position. In 2003 and 2002, Aon settled some of these liabilities. The settlements had no material effect on our consolidated financial statements. (See notes 1 and 6 to the consolidated financial statements for more information on discontinued operations.)

Consolidated Results for Fourth Quarter 2003 Compared to Fourth Quarter 2002

        Total revenues in the quarter rose 10% to $2.6 billion. Excluding the impact of changes in foreign exchange rates, revenue climbed 4%. The higher revenue is primarily due to:

•

very good results from the international risk and insurance brokerage area, combined with improvement in U.S. brokerage and reinsurance



•

growth in new business and improved renewal rates



•

growth in some warranty and credit programs, along with specialty property and casualty lines



•

increased investment income in the Corporate and Other segment, reflecting the change in value of warrants we held in Endurance of $16 million.

        Income from continuing operations before income taxes and minority interest increased by $56 million or 19% over 2002. Both this and last year's results include settlements for various World Trade Center claims. The net change year-over-year for these settlements increased pretax income in 2003 by $49 million.

        This income growth was partially offset by:

•

an increase in costs for our major defined benefit pension plans, which increased the expense for the quarter by $34 million



•

a net charge in the warranty, credit, and property and casualty sub-segment of $44 million for additional losses and reserve strengthening for the NPS run-off program.

Consolidated Results for 2002 Compared to 2001

Revenue

        Total revenues were $8.8 billion, an increase of 15%. Excluding the effects of foreign exchange rates, revenues increased 14% over the comparable period. This increase results from improvements in brokerage commissions and fees, premiums earned, and investment income.

        U.S. revenues, which represent 57% of total revenue, increased 13% in 2002 compared to 2001 as a result of strong organic growth resulting from:

•

commercial property and casualty premium rate increases



•

client demand for risk retention programs and services.

        U.K. and Continent of Europe revenues combined increased 18% to $2.7 billion and Rest of World revenue increased 19%, reflecting strong new business and increasing premium rates, which increase commissions, and foreign exchange.

        Brokerage commissions and fees increased 14% to $6.2 billion, primarily from organic growth including increased premium rates, increased new business, and outsourcing contracts. This growth was offset somewhat by revenue disruptions in the early part of the year with our managing general underwriter unit. Acquisitions contributed $90 million of incremental revenue in 2002.

35

        Premiums and other increased 17% in 2002 to $2.4 billion. This increase primarily reflects growth in new business initiatives, traditional accident and health lines, and new specialty property and casualty lines. This increase was somewhat offset by the prior loss of some accounts in the warranty business.

        Investment income increased by 18% over 2001, despite a drop in interest rates. The increase was driven by:

•

improved returns on limited partnerships and other private equity investments accounted for on the equity method in 2002



•

$48 million of interest income received from the settlement of a prior year tax issue.

        These improvements were offset by impairment write-downs for certain directly owned investments, including those classified as other-than-temporary, which were $73 million higher than the prior year. Investment income from our Risk and Insurance Brokerage Services and Consulting segments, primarily relating to funds held on behalf of clients, decreased $49 million compared to 2001, largely due to declining interest rates.

Expenses

        General expenses increased 13% over 2001 reflecting:

•

growth of the businesses



•

higher costs in the U.S. retail brokerage business



•

increased risk management and litigation reserve items



•

higher overall pension plan costs



•

costs related to the planned spin-off.

        Benefits to policyholders rose $264 million or 24% due to new business volume increases, an increased payout ratio of benefits to policyholders versus net premiums earned, issues related to NPS and a shift in business mix to products with higher benefit payout ratios.

        Interest expense was down slightly due to lower short-term interest rates.

        Amortization of intangible assets declined $104 million from 2001 as goodwill was not amortized in 2002 in accordance with FASB Statement No. 142.

Income from Continuing Operations Before Income Tax and Minority Interest

        Income from continuing operations before income tax and minority interest increased significantly from $368 million in 2001 to $824 million in 2002. This increase is due primarily to the net change in expenses related to the World Trade Center ($187 million), the business transformation plan ($224 million) and the improvement in Corporate and Other revenue ($150 million). Approximately 76% of Aon's 2002 consolidated income from continuing operations before income tax and minority interest was from international operations.

Income Taxes

        The effective tax rate was 39.5% for 2001 and 37% for 2002. The decline from 2001 was due to the non-deductibility of certain goodwill, which, beginning in 2002, is no longer amortized for book purposes. The overall effective tax rates are higher than the U.S. federal statutory rate primarily because of state income tax provisions.

36

Income from Continuing Operations

        Income from continuing operations increased to $486 million ($1.71 per dilutive share) from $183 million ($0.66 per dilutive share) in 2001. Basic income from continuing operations per share was $1.72 and $0.67 for 2002 and 2001, respectively. To compute income per share, we have deducted dividends paid for the redeemable preferred stock from net income.

REVIEW BY SEGMENT

General

        Aon classifies its businesses into three operating segments: Risk and Insurance Brokerage Services, Consulting, and Insurance Underwriting. (See note 16 to the consolidated financial statements.) Aon's operating segments are identified as those that:

•

report separate financial information



•

are evaluated regularly when we are deciding how to allocate resources and assess performance.

        We attribute revenues to geographic areas based on the location of the resources producing the revenues.

        Segment revenue includes investment income, as well as the impact of related derivatives, generated by operating invested assets of that segment. Investment characteristics mirror liability characteristics of the respective segments:

•

Our Risk and Insurance Brokerage Services and Consulting businesses invest funds held on behalf of clients and operating funds in short-term obligations



•

In Insurance Underwriting, policyholder claims and other types of non-interest sensitive insurance liabilities are primarily supported by intermediate to long-term fixed-maturity instruments. Investments underlying interest-sensitive capital accumulation insurance liabilities are fixed- or floating-rate fixed-maturity obligations. For this business segment, operating invested assets are approximately equal to average net policy liabilities.



•

Our insurance subsidiaries also have invested assets that exceed net policy liabilities in order to maintain solid claims paying ratings. Income from these investments are reflected in Corporate and Other segment revenues.

37

        The following tables and commentary provide selected financial information on the operating segments.

(1)

Intersegment revenues of $68 million were eliminated in 2003. See note 16 to the consolidated financial statements.

Risk and Insurance Brokerage Services

        Aon is a leader in many sectors of the insurance industry: globally, it is the second largest insurance broker, the largest reinsurance broker and the leading manager of captive insurance companies worldwide. In the U.S., Aon is the largest wholesale broker and underwriting manager. These rankings are based on the most recent surveys compiled and reports printed by Business Insurance.

        The devastation caused by the attacks of September 11, 2001 resulted in the largest insurance loss in history. At the same time, there was an unprecedented escalation of insurance premium rates because of larger than anticipated loss experience across most risks, the stock market's steep decline, lower interest rates, and diminished risk capacity.

        Higher premium rates, or a "hard market," generally result in increased commission revenues. Changes in premiums have a direct and potentially material impact on the insurance brokerage industry, as commission revenues are generally based on a percentage of the premiums paid by insureds. However, it is difficult to predict the longevity of the hard market, and the rate of increase in premiums in the property and casualty marketplace has already begun to level off.

        Risk and Insurance Brokerage Services generated approximately 58% of Aon's total operating segment revenues in 2003. Revenues are generated primarily through:

•

commissions and fees paid by insurance and reinsurance companies



•

fees paid by clients



•

certain other carrier compensation



•

interest income on funds held on behalf of clients.

        Our revenues vary from quarter to quarter throughout the year as a result of:

•

how our clients' policy renewals are timed



•

the net effect of new and lost business



•

the timing of services provided to our clients

38

•

the income we earn on investments, which is heavily influenced by short-term interest rates.

        With the exception of employee incentives, expenses generally tend to be more uniform throughout the year.

        Our retail brokerage companies operate in a highly competitive industry and compete with a large number of retail insurance brokerage and agency firms, as well as individual brokers and agents and direct writers of insurance coverage. Specifically, this segment:

•

addresses the highly specialized product development and risk management needs of professional groups, insurance companies, service businesses, governments, healthcare providers, commercial organizations and non-profit groups, among others



•

provides affinity products for professional liability, life, disability income and personal lines for individuals, associations and businesses



•

provides wholesale brokerage, managing underwriting and premium finance services to independent agents and brokers as well as corporate clients



•

offers claims management and loss cost management services to insurance companies and firms with self-insurance programs



•

provides actuarial, loss prevention and administrative services to businesses and consumers.

        We review our product revenue results using the following sub-segments:

•

Risk Management and Insurance Brokerage—Americas (Brokerage—Americas) encompasses our retail and wholesale brokerage services, affinity products, managing general underwriting, placement and captive management services, and premium finance services in North and South America, the Caribbean and Bermuda.



•

Risk Management and Insurance Brokerage—International (Brokerage—International) offers similar products and services to the rest of the world not identified above.



•

Reinsurance Brokerage and Related Services (Reinsurance) offers sophisticated advisory services in program design and claim recoveries that:



•

enhance the risk/return characteristics of insurance policy portfolios



•

improve capital utilization



•

evaluate and mitigate catastrophic loss exposures worldwide.



•

Claim Services (Claims) offers claims administration and loss cost management services.

        The Risk and Insurance Brokerage Services segment revenues are influenced by the premiums paid by clients to insurers because we receive a percentage of the premiums as a commission in most cases. The availability of insurance coverage can also affect our revenues. If insurance coverage cannot be placed, we do not receive a commission.

39

Revenue

        Total 2003 Risk and Insurance Brokerage Services revenue was $5.7 billion, up 14% on a reported basis over last year. Excluding the effect of foreign exchange rates, revenue rose 8% over last year. Operating revenue, on an organic basis, grew approximately 9% in a very competitive environment. Investment income decreased $34 million in 2003 from reduced derivative gains and lower interest rates.

        Continuing the trend from last year, increases in insurance premium rates benefited revenues in 2003. After September 11, 2001 insurance markets, whose premium rates were rising already, rose further as a result of restrictions on the availability of some coverages and the pressure on the financial strength of some insurance companies. The property and casualty insurance market is very competitive. As premium rates rise, clients often retain more risk. This dynamic has, and may continue to, limit revenue growth for pure brokerage services, but it provides opportunities to offer more captive insurance and claims management services, as well as safety and loss control services.

        This chart details Risk and Insurance Brokerage Services revenue by sub-segment.

        This chart reconciles organic revenue growth to reported revenue growth.

•

Brokerage-Americas revenue improved due to organic growth, reflecting improved renewal rates and increased new business in the retail brokerage business. Organic growth in the wholesale business was under pressure due to pricing pressures.



•

Brokerage-International revenue showed strong improvement as a result of a favorable foreign exchange impact and strong organic growth.



•

Reinsurance revenue growth reflected strong results in U.S. reinsurance, driven by new business from existing clients and growth in renewal volumes, along with moderate growth internationally, as well as a favorable foreign exchange impact.



•

Claims revenue has increased over last year primarily as a result of a positive foreign exchange impact and higher U.K. volume.

40

        This chart shows Risk and Insurance Brokerage Services revenue by geographic area and pretax income:

•

U.S. revenue has shown a modest increase over 2002. The U.S. reinsurance business posted strong improvement as a result of new business and high renewal volumes. The managing underwriting group has recovered from very depressed results in the prior year. U.S. retail brokerage grew during the year, driven primarily by new business development and improved renewal rates. These increases, however, were partially offset by a decline in claims services revenue.



•

U.K. and Continent of Europe revenue increased primarily as a result of foreign exchange rates and organic revenue growth that reflected new business and good renewal rates.



•

Rest of World revenue increased significantly due to foreign exchange rates, increased market share primarily in the Asian markets, and new business initiatives.

Income Before Income Tax

        Pretax income increased $38 million or 5% from 2002 to $829 million. The improvement in income was realized by the growth in revenues as well as a revised cost methodology which decreased centrally allocated costs by $28 million. In 2003, pretax margins in this segment were 14.6%, down from 15.9% in 2002.

        Our income and margins were impacted this year by:

•

additional pension expense of $109 million



•

a decline in claims services pretax income of $48 million



•

a decline in investment income of $34 million.

        In addition, some events did not hurt our income in 2003, but did affect our year-over-year comparison. These events include:

•

$29 million from a partial settlement in 2002 with Aon's insurance carriers related to the World Trade Center



•

a $6 million credit for the reversal in 2002 of business transformation plan expenses previously incurred for termination benefits with no corresponding amounts in 2003.

Consulting

        Aon Consulting is one of the world's largest integrated human capital consulting organizations. This segment:

•

provides a full range of human capital management services from employee benefits to compensation consulting

41

•

generated 12% of Aon's total operating segment revenues in 2003.

        Consulting services are delivered to corporate clients through five major practice areas:

1.

Employee Benefits advises clients regarding the structure, funding and administration of employee benefit programs which attract, retain and motivate employees.



2.

Compensation focuses on designing salary, bonus, commission, stock option and other pay structures, with special expertise in the financial services and technology industries.



3.

Management Consulting assists clients in process improvement and design, leadership, organization and human capital development, and change management.



4.

Communications advises clients on how to communicate initiatives that support their corporate vision.



5.

Human Resource Outsourcing offers employment processing, performance improvement, benefits administration, and other employment-related services.

        Revenues in the Consulting segment are affected by changes in clients' industries, including government regulation, as well as new products and services, the state of the economic cycle, broad trends in employee demographics and the management of large organizations.

Revenue

        In 2003, revenues of $1.2 billion increased 13% over 2002. Excluding the impact of foreign exchange rates, the growth rate was 9%. Revenue on an organic basis grew 5% from last year. The organic revenue growth resulted from:

•

growth in U.S. compensation and international practices



•

the full year impact of a sizable human resources outsourcing agreement.

        In third quarter 2002, Aon entered into a sizeable new outsourcing contract with AT&T that is expected to provide favorable returns over the life of the multi-year agreement. The recognition of revenues and expenses, however, will significantly influence financial results over the contract period. Revenues are recorded on a gross basis, inclusive of amounts ultimately passed through to subcontractors, and are recorded ratably over the life of the contract. Up-front investment costs to support the new business cause pretax margins to be significantly lower in the early years of the multi-year contract, compared with the later years when margins are expected to increase. A significant portion of the up-front investment costs incurred for the new outsourcing contracts can be leveraged to handle increased business volume.

        This chart details Consulting revenue by sub-segment.

42

        This chart reconciles organic revenue growth to reported revenue growth.

•

The increase in benefits, compensation, management and communication consulting revenue was driven by positive foreign exchange rates and organic revenue growth in U.S. compensation and benefits and international practices. This increase was partially offset by a decline in management consulting.



•

Human resource outsourcing revenue improvement was due to the large contract initiated in third quarter 2002.

        This chart shows Consulting revenue by geographic area and pretax income:

•

U.S. revenue posted a strong increase in 2003, primarily reflecting the human resources outsourcing agreement initiated in third quarter 2002.



•

U.K., Continent of Europe and Rest of World revenues rose on favorable currency exchange impacts and organic revenue growth.

Income Before Income Tax

        Pretax income was $108 million, a 10% decline from last year. In 2003, pretax margins in this segment were 9.1%, down from 11.4% in 2002. Margins in this segment were reduced by:

•

a revised cost allocation methodology, resulting in higher expense allocations of $16 million over 2002



•

increased pension and insurance costs



•

a non-recurring stock-based expense adjustment.

        The pretax margins for 2003 were also influenced by a lower margin human resources outsourcing contract, as discussed above.

43

Insurance Underwriting

        The Insurance Underwriting segment:

•

provides supplemental accident, health and life insurance coverage mostly through direct distribution networks, primarily through more than 7,600 career insurance agents working for our subsidiaries. Our revenues are affected by our success in attracting and retaining these career agents. The agency force turnover has remained fairly stable over time. The sales management team is a strength that enables the recruiting model to remain effective.



•

provides supplemental Medicare policies in the U.S. through a dedicated sales force



•

offers extended warranty and credit insurance products that are sold through retailers, automotive dealers, insurance agents and brokers, and real estate brokers. Our revenues are also affected by the addition and retention of these retailers, dealers, agents and brokers.



•

offers select commercial property and casualty business on a limited basis through managing general underwriters, primarily Aon-owned companies



•

provides the administration of certain extended warranty services on automobiles, electronic goods, personal computers and appliances



•

has operations in the United States, Canada, Latin America, Europe and Asia/Pacific



•

generated approximately 30% of Aon's total operating segment revenues in 2003.

        In the accident, health and life operations, we provide an array of accident, sickness, short-term disability and other supplemental insurance products. Most of these products are primarily fixed-indemnity obligations, and are not subject to escalating medical cost inflation.

        We have:

•

developed relationships with select brokers and consultants to reach specific niche markets



•

expanded product distribution to include direct response programs, affinity groups, and worksite marketing, which has created access to new markets and potential new policyholders



•

implemented a "back-to-basics" strategy, focusing on products and regions with predictable cash flows and the best return on investment



•

announced plans in February 2003 to place in run-off our accident and health insurance underwriting operations in Latin America. We stopped operations in Argentina and have transitioned into run-off status in Brazil and Mexico during 2003.



•

transferred the large employer group life and accidental death business to a third party via an indemnity reinsurance arrangement



•

decided to run off certain non-core special risk accident and health business in the U.K.

        Our warranty and credit subsidiaries in North America, Latin America, Europe and Asia/Pacific provide warranties on automobiles and a variety of consumer goods, including electronics and appliances. In addition, we provide non-structural home warranties and other warranty products, such as credit card enhancements and affinity warranty programs.

Revenue

        Written premiums and fees are the basis for organic revenue growth in this segment; however, reported revenues reflect earned premiums.

44

        A table reflecting written and earned premiums and associated reserves follows:

        In 2003, revenues of $2.9 billion increased 3% over 2002. Excluding the effect of foreign exchange rates, revenues were flat year-over-year.

        This chart details Insurance Underwriting revenue by sub-segment.

        This chart reconciles organic revenue growth to reported revenue growth.

(1)

The difference between written and earned premiums and fees, as a percentage change, was 0% for accident & health, (2)% for warranty and (1)% for total revenue. The change in warranty and total revenue also resulted from a one-time assumption of premiums ceded from a client's captive in 2002.

45

•

Revenue declined in accident & health and life for 2003 primarily due to our decision to:



—

pursue a "back-to-basics" strategy in the core businesses



—

run off the accident and health insurance underwriting operations in the Latin American countries and to transfer our U.S. large employer group life business. These businesses generated approximately $14 million of revenues and $6 million of pretax losses in 2003 compared to $94 million in revenues and $22 million of pretax losses in 2002. We are exiting these businesses and expect to completely withdraw in 2005. We also decided to run off certain non-core special risk accident and health business in the U.K.



•

Growth in the select property and casualty business, as well European credit and warranty programs, drove the revenue improvement in warranty, credit and property & casualty.

        Overall core business growth was partially offset by:

•

a decline in investment income of $47 million, significantly impacted by a $27 million decline in interest earned on investments underlying deposit-type contracts, as that business has been placed in run-off



•

overall lower interest rates.

        This chart details Insurance Underwriting revenue by geographic area and pretax income:

•

In 2003, U.S. revenue declined primarily as a result of the runoff of our U.S. large employer group life and accidental death business.



•

U.K., Continent of Europe, and Rest of World posted significant revenue improvement during the year. This increase is primarily the result of a favorable currency exchange rate impact and organic revenue growth in European direct sales, warranty and credit operations.

Income Before Income Tax

        Pretax income of $196 million increased 26% from 2002. Pretax margins rose from 5.5% in 2002 to 6.8% in 2003.

        Increased pretax income and margin resulted from:

•

higher expenses and charges concerning the planned divestiture of the Insurance Underwriting segment of $33 million in 2002, with no corresponding amounts in 2003



•

improved profitability in the traditional lines of accident & health and life



•

provision for non-claims litigation issues of $15 million in 2002, with no corresponding amount in 2003



•

reduced losses in Europe warranty and improvements in property & casualty, excluding NPS.

46

        These increases were partially offset by:

•

charges related to losses and reserve strengthening for the NPS run-off program, which were $65 million in 2003 versus a $36 million charge in 2002



•

a revised cost allocation methodology, which resulted in increased expense allocations of $12 million for 2003.

Corporate and Other

        Corporate and Other segment revenue consists primarily of investment income (including income or loss on disposals, including other-than-temporary impairment losses), which is not otherwise reflected in the operating segments. This segment includes:

•

invested assets and related investment income not directly required to support the risk and insurance brokerage services and consulting businesses



•

the assets in excess of net policyholder liabilities of the insurance underwriting subsidiaries and related income.

        Corporate and Other segment revenue includes income from Endurance common stock, accounted for under the equity method, and changes in the valuation of Endurance warrants. Aon carries its investment in Endurance warrants at fair value and records changes in the fair value through Corporate and Other segment revenue, in accordance with FASB Statement No. 133.

        Private equities are principally carried at cost except where Aon has significant influence, in which case they are carried under the equity method. These investments usually do not pay dividends.

        Limited partnerships (LP) are accounted for under the equity method and changes in the value of the underlying LP investments flow through Corporate and Other segment revenue. Because the LP investments include exchange-traded securities, Corporate and Other segment revenue fluctuates with the market values of underlying publicly traded equity investments. LP investments have historically provided higher returns over a longer time than broad market common stock. However, in the short run, the returns are inherently more variable. In December 2001, we securitized $450 million of our LP investments plus associated LP commitments, which represented the majority of our LP interests. This transaction has lessened the variability of revenue reported in this segment. (See note 7 to the consolidated financial statements for additional information regarding the securitization.)

        Although our portfolios are highly diversified, they still remain exposed to market, equity, and credit risk.

        We:

•

periodically review securities with material unrealized losses and evaluate them for other-than- temporary impairments.



•

analyze various risk factors and determine if any specific asset impairments exist. If we determine there is a specific asset impairment, we recognize a realized loss and adjust the cost basis of the impaired asset to its fair value.



•

review invested assets with material unrealized losses each quarter. (See note 7 to the consolidated financial statements for additional information regarding other-than-temporary impairments.)

47

        This chart shows the components of Corporate and Other revenue and expenses: