UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 11-K [X] ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2001 or [ ] TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to ---------------- -------------------- Commission File Number: 1-9894 A. Full title of the plan and address of the plan, if different from that of the issuer named below: ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN B. Name of issuer of the securities held pursuant to the plan and the address of its principal executive office: ALLIANT ENERGY CORPORATION 4902 North Biltmore Lane Madison, Wisconsin 53718 Page 1 of 21 pages Exhibit Index is on page 20 REQUIRED INFORMATION The following financial statements and schedules of the Alliant Energy Corporation 401(k) Savings Plan, prepared in accordance with the financial reporting requirements of the Employee Retirement Income Security Act of 1974, as amended, are filed herewith. 2 ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN FINANCIAL STATEMENTS FOR THE YEARS ENDED DECEMBER 31, 2001 AND 2000, SUPPLEMENTAL SCHEDULES FOR THE YEAR ENDED DECEMBER 31, 2001, AND INDEPENDENT AUDITORS' REPORTS 3 ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN TABLE OF CONTENTS Page No. INDEPENDENT AUDITORS' REPORTS 5-6 FINANCIAL STATEMENTS Statements of Net Assets Available for Plan Benefits as of December 31, 2001 and 2000 7 Statement of Changes in Net Assets Available for Plan Benefits for the Year Ended December 31, 2001 8 NOTES TO FINANCIAL STATEMENTS 9-15 SUPPLEMENTAL SCHEDULES Form 5500, Schedule H, Part IV, line 4i - Schedule of Assets (Held At End of Year) as of December 31, 2001 16 Form 5500, Schedule H, Part IV, line 4i - Schedule of Assets (Acquired and Disposed of Within Year) for the Year Ended December 31, 2001 17 Form 5500, Schedule H, Part IV, line 4j - Schedule of Reportable Transactions for the Year Ended December 31, 2001 18 SIGNATURES 19 EXHIBIT INDEX 20 Independent Auditors' Consent 21 4 Independent Auditors' Report To the Plan Administrator of the Alliant Energy Corporation 401(k) Savings Plan: We have audited the accompanying statement of net assets available for plan benefits of the Alliant Energy Corporation 401(k) Savings Plan (the "Plan") as of December 31, 2001 and the related statement of changes in net assets available for plan benefits for the year then ended. These financial statements are the responsibility of the Plan's management. Our responsibility is to express an opinion on these financial statements and supplemental schedules based on our audit. We conducted our audit in accordance with auditing standards generally accepted in the United States of America. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audit provides a reasonable basis for our opinion. In our opinion, such 2001 financial statements referred to above present fairly, in all material respects, the net assets available for plan benefits of the Plan as of December 31, 2001, and the changes in net assets available for plan benefits for the year ended December 31, 2001, in conformity with accounting principles generally accepted in the United States of America. Our audit was conducted for the purpose of forming an opinion on the basic 2001 financial statements taken as a whole. The supplemental schedules listed in the Table of Contents are presented for the purpose of additional analysis and are not a required part of the basic financial statements, but are supplementary information required by the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. These schedules are the responsibility of the Plan's management. Such schedules have been subjected to the auditing procedures applied in our audit of the basic 2001 financial statements and, in our opinion, are fairly stated in all material respects when considered in relation to the basic financial statements taken as a whole. /s/ Deloitte & Touche LLP Milwaukee, Wisconsin July 3, 2002 5 Arthur Andersen LLP (Andersen) is the former auditor of the Alliant Energy Corporation 401(k) Savings Plan (the Plan). As a result of recent events at Andersen, Andersen declined the Plan's request to reissue their audit report dated June 1, 2001 for the fiscal years ended December 31, 2000 and 1999 for inclusion in the Plan's 11-K filing for the fiscal year ended December 31, 2001. As such, pursuant to the guidance given in the Temporary Final Rule and Final Rule: Requirements for Arthur Andersen LLP Auditing Clients, Release Nos. 33-8070; 34-45590; 35-27503; 39-2395; IA-2018; IC-25464; FR-62; File No. S7-03-02, the Plan is filing this copy of the latest signed and dated accountant's report issued by Andersen for such periods. Report of Independent Public Accountants To the Plan Administrator of the Alliant Energy Corporation 401(k) Savings Plan: We have audited the accompanying statements of net assets available for plan benefits of the Alliant Energy Corporation 401(k) Savings Plan (the "Plan") as of December 31, 2000 and 1999, and the related statement of changes in net assets available for plan benefits for the year ended December 31, 2000. These financial statements and the supplemental schedules referred to below are the responsibility of the Plan's administrator. Our responsibility is to express an opinion on these financial statements and supplemental schedules based on our audits. We conducted our audits in accordance with generally accepted auditing standards. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion. In our opinion, the financial statements referred to above present fairly, in all material respects, the net assets available for plan benefits of the Plan as of December 31, 2000 and 1999, and the changes in net assets available for plan benefits for the year ended December 31, 2000, in conformity with generally accepted accounting principles. Our audits were performed for the purpose of forming an opinion on the basic financial statements taken as a whole. The supplemental schedules, as listed in the accompanying table of contents, are presented for purpose of additional analysis and are not a required part of the basic financial statements but are supplementary information required by the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. These supplemental schedules are the responsibility of the Plan's management. The supplemental schedules have been subjected to the auditing procedures applied in the audits of the basic financial statements and, in our opinion, are fairly stated in all material respects in relation to the basic financial statements taken as a whole. /s/ ARTHUR ANDERSEN LLP Milwaukee, Wisconsin June 1, 2001 6 ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN STATEMENTS OF NET ASSETS AVAILABLE FOR PLAN BENEFITS December 31, 2001 2000 --------------------- -------------------- Investment income receivable $3,862,243 $2,295,832 Contributions receivable 1,100,180 - Loan payment receivable - 37,280 --------------------- -------------------- Total receivables 4,962,423 2,333,112 --------------------- -------------------- Investments, other than participant promissory notes (Refer to Note 7) 329,894,234 396,861,094 Participant promissory notes 7,686,036 9,563,617 --------------------- -------------------- Total investments 337,580,270 406,424,711 --------------------- -------------------- Net assets available for plan benefits $342,542,693 $408,757,823 ===================== ==================== The accompanying Notes to Financial Statements are an integral part of these statements. 7 ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN STATEMENT OF CHANGES IN NET ASSETS AVAILABLE FOR PLAN BENEFITS For the Year Ended December 31, 2001 Net assets available for plan benefits - beginning of year $408,757,823 Contributions: Cash contributions from employees 24,300,679 Rollovers from other qualified plans 733,210 Employer contributions: Cash 721,556 Cash for purchase of Alliant Energy Corporation common stock 7,128,868 Investment activity: Investment income 9,680,299 Net depreciation in fair value of investments (Refer to Note 7) (51,380,764) Distributions: Transfers to other plans (Refer to Note 10) (39,756,912) Distributions to participants (17,642,066) -------------------- Net assets available for plan benefits - end of year $342,542,693 ==================== The accompanying Notes to Financial Statements are an integral part of this statement. 8 ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN NOTES TO FINANCIAL STATEMENTS YEARS ENDED DECEMBER 31, 2001 AND 2000 Note 1. Description of the Plan The Alliant Energy Corporation 401(k) Savings Plan (the Plan) is a qualified defined contribution plan under Section 401(k) of the Internal Revenue Code (the Code), as amended, and meets the applicable requirements of the Employee Retirement Income Security Act of 1974, as amended. The following brief description of the Plan is provided for general information purposes only. More complete information regarding the Plan benefits is provided in the summary plan description which has been made available to all eligible Plan participants. The Plan is administered by the Employee Total Compensation Committee (the Committee) and the Plan sponsor is Alliant Energy Corporate Services, Inc. (a direct subsidiary of Alliant Energy Corporation) which reserves the right to terminate, amend or modify the Plan if future conditions warrant such action. Any regular employee of Alliant Energy Corporation and its participating subsidiaries (the Company) age 18 and over may become a participant in the Plan. Regular full-time employees and regular part-time employees customarily scheduled to work at least half-time may participate on the first day of any calendar month following 30 consecutive days of service. Part-time employees customarily scheduled to work less than half-time may participate after 12 months of service during which he or she has earned at least 1,000 paid hours. Certain Interstate Power and Light Company bargaining employees, members of the bargaining units of the former Interstate Power Company, must complete the one-year (1,000 hour) waiting period. (On January 1, 2002, Interstate Power Company merged with and into IES Utilities Inc. and IES Utilities Inc. changed its name to Interstate Power and Light Company, resulting in no changes to the Plan.) Wisconsin Power and Light Company "special temporary" bargaining employees are also eligible under the same rules as "regular" employees. The Company provides guaranteed matching contributions for each $1 contributed by participants up to a maximum of the first 6% of the participants' compensation. Other than the exceptions noted below, employee contribution limits and employee match information for 2001 are as follows: Company match for each $1 contributed up to the maximum $0.50 Eligible employee annual contribution limit as a percentage of compensation 19% Maximum annual contribution limit $10,500 The matching contributions for Alliant Energy Resources, Inc. (Resources) and Cedar Rapids and Iowa City Railway Company (CRANDIC) employees are calculated based on a percentage of base pay, without overtime or incentive pay, and there is a "basic" Company contribution equal to 4% and 2%, respectively, of base pay. Company matching contributions for Resources and CRANDIC employees are invested at the participants' discretion. All other matching contributions by the Company are invested in the Alliant Energy Corporation Common Stock Fund. 9 Resources and CRANDIC employees may be eligible for a discretionary Company contribution of $0.50 for every $1 contributed up to a maximum of the first 6% of pay in addition to the "basic" Company contribution. The discretionary contribution for both Resources and CRANDIC employees is based on goals established by Resources and is evaluated during the first quarter of the following year. Beginning with the 2001 Plan year, an additional Company contribution is allocated to the accounts of active Plan participants, except for Resources and CRANDIC employees, as of the last day of the Plan year, who had contributed 6% of compensation during the Plan year and did not receive a Company matching contribution equal to 3% of compensation. The amount of the additional Company contribution is the difference between 3% of compensation during the Plan year and the amount of Company matching contributions previously received during the Plan year. Participants are immediately vested in their employee and employer contributions. Contributions under the Plan are held and invested, until distribution, in a Trust Fund maintained by American Express Trust Company (the Trustee), a division of American Express Financial Advisors Inc. The investment options available to participants are Stable Capital Fund, PIMCO Total Return Fund, Janus Adviser Balanced Fund, American Express Trust Equity Index Fund III, American Century Income & Growth Fund, AXP Growth Fund, Franklin Small - Mid Cap Growth Fund, Marshall International Stock Fund, Alliant Energy Corporation Common Stock Fund, or a combination of the nine funds. Additionally, participants may subsequently redesignate the distribution of future contributions or transfer existing balances between investment funds on a daily basis, subject to the limits set forth in the Plan. Company matching contributions invested in the Alliant Energy Corporation Common Stock Fund may not be transferred to any other investment fund, except for contributions made for CRANDIC and Resources employees as previously described; however, Company matching contributions may be transferred by certain participants during the 30-day period immediately prior to retirement. A brief description of the investment options is as follows: Stable Capital Fund. The Stable Capital Fund is a stable value fund. Its objective is to preserve principal while seeking a competitive level of current income. The Stable Capital Fund is intended to be a lower risk investment with a higher return than is typically offered by money market funds, while it maintains liquidity and safety of principal. The fund is invested primarily in Guaranteed Investment Contracts (GIC's) issued by one or more insurance companies or other financial institutions. The fund may also invest in the American Express Trust Income Fund I and the American Express Trust Money Market Fund I. The carrying value of all GIC investments was $34,216,008 and $33,831,298 at December 31, 2001 and 2000, respectively. The approximate fair value of these investments was $34,792,937 and $36,416,741 at December 31, 2001 and 2000, respectively, based on the discounted cash flows valuation method. Under the terms of the GIC's, the average crediting interest rate was 5.87% and 6.61% on December 31, 2001 and 2000, respectively, and is fixed for all contracts. The GIC's earned an average rate of 6.55% in 2001. PIMCO Total Return Fund. The PIMCO Total Return Fund is an actively managed, intermediate maturity bond portfolio. Its objective is to maximize total return, consistent with preservation of capital and prudent investment management, in order to exceed the returns of the bond market as a whole as represented by the Lehman Brothers Aggregate Bond Index. The average duration ranges between 3 and 6 years. Janus Adviser Balanced Fund. Effective June 1, 2001, the Janus Adviser Balanced Fund replaced the Dreyfus Founders Balanced Fund. Participants who had monies invested in the Dreyfus Founders Balanced Fund had their current and future contributions transferred to the Janus Adviser Balanced Fund. The Janus Adviser Balanced Fund is a growth and income fund. Its objective is to seek long-term capital growth, consistent with preservation of capital and balanced by current income. It normally invests 40% to 60% of its assets in securities selected primarily for their growth potential and 40% to 60% of its assets in securities selected primarily for their income potential. At least 25% of the fund's assets are normally invested in fixed income senior securities, which include debt securities and preferred stocks. 10 American Express Trust Equity Index Fund III. American Express Trust Equity Index Fund III is a growth and income fund. Its objective is to provide investment results that correspond to the price and yield performance of publicly traded stocks, in aggregate, as represented by the Standard & Poors' 500 Composite Stock Price Index. American Century Income & Growth Fund. American Century Income & Growth Fund is a large-cap value fund. Its objective is to seek dividend growth, current income and capital appreciation by investing in securities of the 1,500 largest companies traded in the United States. The fund may also invest in foreign securities. AXP Growth Fund. The AXP Growth Fund is a large-cap growth fund. Its objective is to seek capital appreciation by investing in securities of those companies believed to have above-average potential for long-term growth as a result of new management, marketing opportunities or technical superiority. The AXP Growth Fund invests primarily in common stocks of medium-to-large capitalization growth companies. Franklin Small - Mid Cap Growth Fund. The Franklin Small - Mid Cap Growth Fund (formerly known as the Franklin Small Cap Growth Fund) is a diversified portfolio which seeks to provide long-term capital appreciation by investing principally in common stocks of companies with market capitalization of less than $1.5 billion. The Franklin Small - Mid Cap Growth Fund's investment strategy emphasizes companies with potential to rapidly grow revenues, earnings, or cash flow. Marshall International Stock Fund. The Marshall International Stock Fund is an international stock fund. Its objective is to seek long-term capital appreciation. The Marshall International Stock Fund invests primarily in stocks and bonds of foreign companies and governments outside the United States. Alliant Energy Corporation Common Stock Fund. This fund is invested primarily in common stock of the Company. A portion of the fund (0-2% of total fund assets) may also be invested in the American Express Trust Money Market Fund I to help provide liquidity for transfers out of the fund. Purchases and sales of common stock are made by the Trustee on the open market. Participant Loans. The Plan has provisions under which participants may take loans up to the lesser of $50,000 or 50% of their total account balance (a $1,000 minimum loan amount and a maximum of three loans for each participant also apply). The Committee determines the loan interest rate pursuant to the Plan. Interest rates on participant loans ranged from 6.0% to 10.5% at December 31, 2001 and 6.75% to 11.00% at December 31, 2000. Note 2. Summary of Significant Accounting Policies (a) Basis of Accounting - The financial statements have been prepared on the accrual basis of accounting. (b) Valuation of Investments and Income Recognition - All GIC's held by the Plan are fully benefit responsive and are valued at contract value, which represents contributions made under the contract, plus interest at the contract rate (less funds used to pay plan benefits). Participant loans are carried at unpaid principal balances due. All other Plan investments are carried at fair value as determined by quoted market prices. Interest income is accrued when earned. Dividend income is recorded on the ex-dividend date. (c) Net Depreciation in Fair Value of Investments - Net realized and unrealized depreciation is recorded in the accompanying statement of changes in net assets available for plan benefits as "Net depreciation in fair value of investments." 11 (d) Payment of Benefits - Benefit payments to participants are recorded when paid. (e) Expenses - Investment management fees are paid from investment earnings prior to crediting earnings to the individual participant account balances. Most other Plan administrative expenses are absorbed by the Company. (f) Use of Estimates - The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires the Plan administrator to make estimates and assumptions that affect the reported amounts of net assets available for plan benefits at the date of the financial statements and the reported amounts of changes in net assets available for plan benefits during the reporting period. Actual results could differ from those estimates. (g) Risk and Uncertainties - The Plan invests in various investments, including pooled investment funds. Investments, in general, are exposed to various risks, such as interest rate, credit, and overall market volatility. Due to the level of risk associated with certain investments, it is reasonably possible that changes in the values of certain investments will occur in the near term and that such changes could materially affect the amounts reported in the financial statements. Note 3. Tax Status The Internal Revenue Service has determined and informed the Company by a letter dated July 31, 1996, that the Plan and related trust are designed in accordance with the applicable sections of the Code. The Plan has been amended since receiving the determination letter and the Company has filed for a new determination letter, however, the Plan administrator and the Plan's tax counsel believe that the Plan is designed and is currently being operated in compliance with the applicable requirements of the Code. It is the intention of the Company to adopt any amendments necessary to maintain the qualified status of the Plan. Note 4. Plan Termination Provisions Upon termination of the Plan in its entirety, each participant is entitled to receive, in accordance with the terms of the Plan, the entire balance in the participant account. Note 5. Withdrawals and Distributions Withdrawals from participants' account balances will be made to participants while they are employed due to an election made by certain participants, reaching age 59-1/2 for certain participants or 70-1/2, or request due to special "hardship" circumstances. Distributions from the Plan will be made upon termination of employment (by retirement, death, disability or otherwise) if the participant's account balance is less than $5,000. If the participant's account balance exceeds $5,000, the participant may elect to defer payment until he or she is age 70-1/2. Distributions can be either in the form of a lump sum or substantially equal annual installments. The unpaid portion of all loans made to the participant, including accrued interest, will be deducted from the amount of the participant account to be distributed. Distributions payable to terminated participants at December 31, 2001 and 2000 were $35,556 and $0, respectively. Distributions payable are not recorded in the accompanying financial statements, however, they are recorded in the Plan's Form 5500 (Refer to Note 11). Note 6. Derivative Financial Instruments The Plan did not invest in any material derivative financial instruments during the years ended December 31, 2001 or December 31, 2000. 12 Note 7. Other Investment Information Investments held which were greater than 5% of the Plan's net assets available for plan benefits as of December 31 were as follows: 2001 2000 ---------------- -------------- Alliant Energy Corporation Common Stock $75,646,312 $69,420,467 (participant directed: $40,347,322 and $39,224,785, respectively) (non-participant directed: $35,298,990 and $30,195,682, respectively) American Express Trust Equity Index Fund III 75,560,203 95,196,553 AXP Growth Fund 55,043,250 91,870,331 Janus Adviser Balanced Fund 28,772,607 N/A Franklin Small - Mid Cap Growth Fund 22,932,386 32,970,044 Dreyfus Founders Balanced Fund N/A 34,378,637 During 2001, the Plan's investments, including gains and losses on investments acquired and disposed of, as well as held during the year, appreciated (depreciated) in value as follows: AXP Growth Fund ($26,085,432) American Express Trust Equity Index Fund III (10,562,528) Franklin Small - Mid Cap Growth Fund (6,061,288) Marshall International Stock Fund (3,678,027) Alliant Energy Corporation Common Stock (3,404,848) Janus Adviser Balanced Fund (1,220,823) Dreyfus Founders Balanced Fund (599,028) American Century Income & Growth Fund (157,027) PIMCO Total Return Fund (36,814) American Express Trust Income Fund I 425,051 ---------------------- Net depreciation in fair value of investments ($51,380,764) ====================== Note 8. Non-Participant Directed Investments Information about the net assets and the significant components of the changes in net assets relating to the non-participant directed investments was as follows: Net Assets: December 31, 2001 December 31, 2000 ---------------------- ---------------------- Alliant Energy Corporation Common Stock $35,298,990 $30,195,682 American Express Trust Money Market Fund I 651,047 1,969,226 Contributions receivable 257,043 -- Investment income receivable 1,409 11,215 ---------------------- ---------------------- $36,208,489 $32,176,123 ====================== ====================== 13 For the year ended Changes in Net Assets: December 31, 2001 ---------------------- Employer contributions $7,128,868 Results of investment activity: Investment income 2,366,710 Net depreciation in fair value of investments (1,655,459) Transfers to participant directed investments (85,332) Transfers to other plans (Refer to Note 10) (2,536,586) Distributions to participants (1,185,835) ---------------------- $4,032,366 ====================== Note 9. Related Party Transactions Certain Plan investments are shares of mutual funds and trust funds managed by an affiliate of the Trustee and shares of common stock of the Company. As of December 31, 2001 and 2000, the Plan held 2,491,644 and 2,177,897 shares of Alliant Energy Corporation common stock, respectively. These transactions qualify as party-in-interest. Note 10. Amendments and Changes to the Plan During 2001, participant accounts for Alliant Energy Corporation employees who became employees of the Nuclear Management Company, LLC (NMC) were transferred from the Plan to a 401(k) plan sponsored by the NMC. The total amount transferred out of the Plan during 2001 was $39,756,912. Alliant Energy Corporation owns interests in two nuclear facilities which the NMC operates under contract. Note 11. Reconciliation to Form 5500 GIC's are recorded in the accompanying financial statements at contract value; however, they are recorded in the Plan's Form 5500 at fair value. In addition, distributions payable to terminated participants are not included in the accompanying financial statements, however, they are recorded in the Plan's Form 5500. The following table reconciles net assets available for plan benefits per the financial statements to the Form 5500 as filed by the Company for the year ended December 31, 2001 and 2000: 2001 2000 -------------------------- -------------------------- Net assets available for plan benefits $342,542,693 $408,757,823 per financial statements Adjustments: Difference between contract value and fair value of GIC's at December 31 -- 2,585,443 Benefits requested not yet paid (35,556) -- -------------------------- --------------------------- Amounts reported per Form 5500 $342,507,137 $411,343,266 ========================== =========================== 14 The following table reconciles changes in net assets available for plan benefits per the financial statements to the Form 5500 as filed by the Company for the year ended December 31, 2001: Net Depreciation in Fair Distributions to Value of Investments Participants --------------------------- --------------------------- Amounts reported per financial statements ($51,380,764) ($17,642,066) Adjustments: Difference between contract value and fair value of GIC's (2,585,443) -- Benefits requested not yet paid -- (35,556) --------------------------- --------------------------- Amounts reported per Form 5500 ($53,966,207) ($17,677,622) =========================== =========================== Note 12. Subsequent Event Effective January 1, 2002, the Company adopted an Employee Stock Ownership Plan (ESOP) within the Plan. Under the new provisions, Plan participants have the option to elect to receive cash for any dividends paid on Company common stock in their Alliant Energy Corporation Common Stock ESOP Fund account or continue to have the dividends reinvested in the Alliant Energy Corporation Common Stock Fund. 15 ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN FORM 5500, SCHEDULE H, PART IV, LINE 4i - SCHEDULE OF ASSETS (HELD AT END OF YEAR) AS OF DECEMBER 31, 2001 Identity of issue, borrower, Description of investment including maturity date, Current lessor, or similar party rate of interest, collateral, par or maturity value Cost Value --------------------------------- ----------------------------------------------------------------- -------------- -------------- Interest Bearing Cash American Express Trust Money Market Fund I *, 1,903,248 shares $1,903,248 $1,903,248 Registered Investment Companies AXP Growth Fund *, 2,038,639 shares 78,650,836 55,043,250 Janus Adviser Balanced Fund, 1,256,446 shares 29,884,311 28,772,607 Franklin Small - Mid Cap Growth Fund, 735,720 shares 31,840,608 22,932,386 Marshall International Stock Fund, 1,137,193 shares 16,712,260 11,815,431 PIMCO Total Return Fund, 1,312,310 shares 13,828,828 13,726,764 American Century Income & Growth Fund, 95,587 shares 2,660,879 2,612,384 Common/Collective Trusts American Express Trust Equity Index Fund III *, 2,549,007 shares 73,709,386 75,560,203 American Express Trust Income Fund I *, 132,299 shares 6,842,286 7,665,641 Corporate Stocks: Common Alliant Energy Corporation common stock *, 2,491,644 shares 65,232,766 75,646,312 Investment Contracts (in Stable Capital Fund) Monumental Life Insurance Company, 5.78%, 12/31/2050 5,000,134 5,257,884 Synthetic Guaranteed Investment Contract Wrapper - (100,045) Bank of America NA, 7.72%, 12/31/2050 4,427,809 4,372,904 Synthetic Guaranteed Investment Contract Wrapper - (203,950) Rabobank International, 6.68%, 12/31/2050 4,171,516 4,119,790 Synthetic Guaranteed Investment Contract Wrapper - (121,018) CDC Financial Products Inc., 5.43%, 12/31/2050 2,895,878 2,859,969 Synthetic Guaranteed Investment Contract Wrapper - (37,734) JP Morgan Chase & Co., 4.81%, 12/31/2050 2,739,677 2,705,705 Synthetic Guaranteed Investment Contract Wrapper - 28,393 UBS Warburg, 5.66%, 12/31/2050 2,641,783 2,609,025 Synthetic Guaranteed Investment Contract Wrapper - (41,427) State Street Bank and Trust Company, 5.00%, 12/31/2050 2,151,981 2,153,289 Synthetic Guaranteed Investment Contract Wrapper - 4,681 AIG Financial Products Corp., 7.22%, 12/31/2050 2,224,908 2,197,319 Synthetic Guaranteed Investment Contract Wrapper - (81,710) United of Omaha, 2.08%, 5/20/2002 2,004,060 2,004,060 John Hancock Life Insurance Company, 7.69%, 3/31/2005 2,115,670 2,115,670 New York Life Insurance Company, 7.41%, 8/15/2005 2,056,032 2,056,032 Hartford, 5.21%, 11/15/2006 2,018,452 2,018,452 Protective Life Insurance Company, 6.12%, 6/15/2006 2,085,083 2,085,083 Sunamerica Life Insurance, 2.64%, 4/3/2002 1,006,534 1,006,534 United of Omaha, 5.45%, 9/9/2004 1,016,873 1,016,873 Participant Promissory Notes Maximum loan--$50,000 Various interest rates -- 6.0% to 10.5% Primarily maturing within 5 years 7,686,036 7,686,036 -------------- -------------- $367,507,834 $341,390,041 (1) ============== ============== (1) The difference between the total current value on this Schedule H, Part IV, Line 4i and the total investments on the Statement of Net Assets Available for Plan Benefits is equal to the total accrued interest on the GICs, which is reported on the Statement of Net Assets Available for Plan Benefits as investment income receivable at December 31, 2001. * Represents party known to be a party-in-interest to the Plan. 16 ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN FORM 5500, SCHEDULE H, PART IV, LINE 4i - SCHEDULE OF ASSETS (ACQUIRED AND DISPOSED OF WITHIN YEAR) FOR THE YEAR ENDED DECEMBER 31, 2001 Description of investment Identity including maturity date, of issue, borrower, lessor, rate of interest, collateral, Cost of Proceeds of or similar party par or maturity value Acquisitions Dispositions ------------------------------------- --------------------------------------------------- ----------------- ----------------- None. 17 ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN FORM 5500, SCHEDULE H, PART IV, LINE 4j - SCHEDULE OF REPORTABLE TRANSACTIONS FOR THE YEAR ENDED DECEMBER 31, 2001 Identity Total Total Adjusted of Party Involved and Total Number Value of Number Net Selling Cost of Net Description of Assets of Purchases Purchases (1) of Sales Price (1) Assets Sold Gain --------------------- ------------ ------------ -------- ------------- ----------- ---- ---------------------------------------------------------------------------------------------------------------------------------- Single Transaction Exceeds 5% of Value: None. ---------------------------------------------------------------------------------------------------------------------------------- Series of Transactions With Same Broker Exceeds 5% of Value: None. ---------------------------------------------------------------------------------------------------------------------------------- Series of Transactions In Same Security Exceeds 5% of Value: American Express Trust Money Market Fund I 329 $36,358,449 282 $41,752,086 $41,752,086 $ - Alliant Energy Corporation Common Stock 41 15,544,311 20 5,913,621 4,779,295 1,134,326 ---------------------------------------------------------------------------------------------------------------------------------- (1) The purchase/selling price was equal to the fair value on the date of purchase/sale. 18 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the Employee Total Compensation Committee, which administers the Plan, has duly caused this Annual Report to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Madison, and State of Wisconsin, on this 15th day of July, 2002. ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN /s/ Pamela J. Wegner --------------------- Pamela J. Wegner The foregoing person is the Executive Vice President-Shared Solutions of Alliant Energy Corporation and the President of Alliant Energy Corporate Services, Inc. 19 EXHIBIT INDEX ALLIANT ENERGY CORPORATION 401(k) SAVINGS PLAN FORM 11-K Page Number in Sequentially Numbered Exhibit No. Exhibit Form 11-K ----------- ------- --------- 23 Independent Auditors' Consent 21 We have not been able to obtain, after reasonable efforts, the written consent from our former independent public accountant, Arthur Andersen LLP, to our incorporation by reference in the Registration Statement on Form S-8 (No. 333-46735) pertaining to the Alliant Energy Corporation 401(k) Savings Plan of their report dated June 28, 2001 with respect to the financial statements and the supplemental schedules of the Alliant Energy Corporation 401(k) Savings Plan included in this Annual Report on Form 11-K for the year ended December 31, 2000, as required by Section 7 of the Securities Act of 1933, as amended. Accordingly, you may be unable to recover amounts sought in any action against Arthur Andersen LLP, the former independent public accountant, pursuant to the Securities Act of 1933 and the regulations thereunder, and therefore any right of recovery may be limited as a result of the lack of that consent. 20