Exhibit (12)(a)
CMS ENERGY CORPORATION
Ratio of Earnings to Combined Fixed Charges and Preferred Dividends
(Millions of Dollars)
<Table>
<Caption>
Year Ended December 31
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2005 2004 2003 2002 2001
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(c) (d) (e)
Earnings as defined (a)
Pretax income from continuing operations $(706) $ 137 $ 16 $(433) $(428)
Exclude equity basis subsidiaries (17) (88) (41) (39) 68
Fixed charges as defined, adjusted to
exclude capitalized interest of $38,
$(25), $9, $16, and $35 million for the
years ended December 31, 2005,
2004, 2003, 2002, and 2001,
respectively (f) 505 649 605 518 577
----- ----- ----- ----- -----
Earnings as defined $(218) $ 698 $ 580 $ 46 $ 217
===== ===== ===== ===== =====
Fixed charges as defined (a)
Interest on long-term debt $ 506 $ 560 $ 531 $ 404 $ 420
Estimated interest portion of lease rental 6 4 7 10 11
Other interest charges 21 49 61 34 83
Preferred dividends 10 11 15 86 98
----- ----- ----- ----- -----
Fixed charges as defined $ 543 $ 624 $ 614 $ 534 $ 612
===== ===== ===== ===== =====
Ratio of earnings to combined fixed
charges and preferred dividends -- 1.12 -- -- --
===== ===== ===== ===== =====
</Table>
NOTES:
(a) Earnings and fixed charges as defined in instructions for Item 503 of
Regulation S-K.
(b) For the year ended December 31, 2005, fixed charges exceeded earnings by
$761 million. Earnings as defined include $1.184 billion of asset
impairment charges.
(c) For the year ended December 31, 2003, fixed charges exceeded earnings by
$34 million. Earnings as defined include $95 million of asset impairment
charges.
(d) For the year ended December 31, 2002, fixed charges exceeded earnings by
$488 million. Earnings as defined include $602 million of asset impairment
charges.
(e) For the year ended December 31, 2001, fixed charges exceeded earnings by
$395 million. Earnings as defined include $323 million of asset impairment
charges.
(f) For 2004, fixed charges, adjusted as defined, include $25 million of
interest cost that was capitalized prior to 2004 and subsequently expensed
in 2004.