<TABLE>
INTERSTATE POWER COMPANY
RATIO OF EARNINGS TO COMBINED FIXED CHARGES AND PREFERRED DIVIDEND REQUIREMENTS
<CAPTION>
Nine Months Ended
Twelve Months Ended December 31, September 30,
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1995 1996 1997 1998 1999 1999 2000
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(Dollars in thousands)
<S> <C> <C> <C> <C> <C> <C> <C>
Net income $27,656 $28,323 $29,167 $18,757 $30,846 $25,331 $21,768
Income taxes 19,453 18,133 17,685 11,093 19,906 16,094 15,910
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Net income before income taxes 47,109 46,456 46,852 29,850 50,752 41,425 37,678
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Interest expense 17,136 16,472 15,610 14,826 15,121 11,202 11,996
Estimated interest component of rent expense 371 431 538 415 644 480 532
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Fixed charges as defined 17,507 16,903 16,148 15,241 15,765 11,682 12,528
Preferred dividend requirements
(pre-tax basis) 4,187 4,040 3,966 3,939 4,084 3,042 3,230
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Fixed charges and preferred dividend
requirements 21,694 20,943 20,114 19,180 19,849 14,724 15,758
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Earnings as defined $64,616 $63,359 $63,000 $45,091 $66,517 $53,107 $50,206
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Ratio of Earnings to Combined Fixed Charges and
Preferred Dividend Requirements (Unaudited) 2.98 3.03 3.13 2.35 3.35 3.61 3.19
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</TABLE>
