FILER: COMPANY DATA: COMPANY CONFORMED NAME: ALLIANT ENERGY CORPORATION CENTRAL INDEX KEY: STANDARD INDUSTRIAL CLASSIFICATION: ELECTRIC AND OTHER SERVICES COMB. [4931] IRS NUMBER: 391380265 STATE OF INCORPORATION: WI FISCAL YEAR END: 12/31 FILING VALUES: FORM TYPE: 35-CERT SEC ACT: SEC FILE NUMBER: 070-9317 FILM NUMBER: BUSINESS ADDRESS: STREET 1: 222 WEST WASHINGTON AVENUE CITY: MADISON STATE: WI ZIP: 53703 BUSINESS PHONE: 608-252-3311 MAILING ADDRESS STREET 1: P. O. BOX 192 CITY: MADISON STATE: WI ZIP: 53701-0192 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington D. C. 20549 PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 File No. 70-9317 REPORT PERIOD January 1, 2001 through March 31, 2001 In the Matter of ALLIANT ENERGY CORPORATION, ET AL ALLIANT ENERGY CORPORATION ("AEC") hereby certifies on behalf of itself and IES Utilities Inc. ("IESU"), Interstate Power Company ("IPC"), and Alliant Energy Corporate Services, Inc. ("Services") that during the period from January 1, 2001 through March 31, 2001 (the "Reporting Period"): 1. For each of the companies participating in the Utility Money Pool during the Reporting Period, the maximum principal amount of short-term borrowings outstanding from the Utility Money Pool, sources other than the Utility Money Pool, and the maximum total short-term borrowings outstanding during the Reporting Period, and the Securities and Exchange Commission ("SEC") borrowing limit for each participant as of the end of the Reporting Period were as follows: Maximum Maximum Other Maximum Money Pool Short-Term Total SEC Company Borrowings Borrowings Borrowings Limit IESU 128,569,447 0.00 128,569,447 150,000,000 IPC 78,613,549 0.00 78,613,549 100,000,000 WP&L (*) 46,585,255 0.00 46,582,255 NA SERVICES 44,393,946 0.00 44,393,946 100,000,000 (*) All borrowings by WP&L from the Money Pool are exempt under Rule 52(a) and are shown here for information purposes only. 2. During the Reporting Period, the weighted average interest rate for borrowings through the Money Pool was 6.08 %. 3. The maximum amount of AEC's short-term borrowings on behalf of itself and the above named participants in the Utility Money Pool during the Reporting Period, and its SEC limit as of the end of the Reporting Period, were as follows: Maximum Maximum Maximum Loans to Corporate Short-Term SEC Money Pool Borrowings Borrowings Limit AEC 230,714,744 206,032,820 361,285,000 475,000,000 Said transactions have been carried out in accordance with the terms and conditions of, and for the purpose represented in, the Form U-1 Application-Declaration, as amended, of AEC, et al, in File 70-9317, and in accordance with the terms and conditions of the SEC's order dated December 15, 2000, permitting said Application-Declaration to become effective. DATED: May 14, 2001 ALLIANT ENERGY CORPORATION IES UTILITIES INC. INTERSTATE POWER COMPANY WISCONSIN POWER AND LIGHT COMPANY ALLIANT ENERGY CORPORATE SERVICES INC. BY: ALLIANT ENERGY CORPORATION BY: _________________________________ Edward M. Gleason Vice President, Treasurer and Corporate Secretary