EXHIBIT 12.1 St. Mary Land & Exploration Company Computation of Ratios of Earnings to Fixed Charges (dollars in thousands) Three Months Ended March 31, Years Ended December 31, ------------------------------- ----------------------------------------------------------- 2002 2001 2001 2000 1999 1998 1997 --------------------- ------ --------------------- ------ ------ ------ ------ Historical Pro Forma(1) Historical Pro Forma(1) ---------- --------- ---------- ---------- Earnings: Income (loss) from continuing operations $ 2,318 $ 1,973 $20,393 $40,459 $38,559 $55,620 $ 82 $ (8,831) $22,621 Income tax expense (benefit) 1,122 955 11,481 21,829 20,738 33,667 (406) (5,415) 12,325 Total fixed charges 619 1,132 251 904 4,561 1,043 1,451 1,854 1,315 Less capitalized interest 90 90 147 473 1,139 548 270 - - ------- ------- ------- ------- ------- ------- ------- -------- ------- Total earnings $ 3,969 $ 3,970 $31,978 $62,719 $62,719 $89,782 $ 857 $(12,392) $36,261 ======= ======= ======= ======= ======= ======= ======= ======== ======= Fixed charges: Interest expense $ 529 $ 1,042 $ 104 $ 431 $ 3,422 $ 495 $ 1,181 $ 1,854 $ 1,315 Capitalized interest 90 90 147 473 1,139 548 270 - ------- ------- ------- ------- ------- ------- ------- ------- ------- -- -- Total fixed charges $ 619 $ 1,132 $ 251 $ 904 $ 4,561 $ 1,043 $ 1,451 $ 1,854 $ 1,315 ======= ======= ======= ======= ======= ======= ======= ======= ======= Ratio of earnings to fixed 6.4 3.5 127.4 69.4 13.8 86.1 0.6(2) (6.7)(2) 27.6 charges Note: For purposes of computing St. Mary Land & Exploration Company's ratios of earnings to fixed charges, "earnings" represent pretax earnings from continuing operations plus fixed charges (excluding capitalized interest). "Fixed charges" represent interest expensed and capitalized. Interest expense includes the portion of operating rental expense that St. Mary believes is representative of the interest component of rental expense. (1) Gives pro forma effect to (a) the use of proceeds from the issuance in March 2002 of $100 million total principal amount of 5.75% senior convertible notes due 2022 to repay $50.45 million in outstanding debt under St. Mary's revolving credit facility and (b) a five-year fixed rate-to-floating rate interest swap entered into with respect to $50 million of the notes. The floating interest rate under the swap for each applicable six-month period will be the London interbank offered rate plus 0.38%. For the initial six-month calculation period this rate is 2.69%. (2) Earnings in 1999 and 1998 were inadequate to cover fixed charges, with a deficiency of $0.6 million and $14.3 million, respectively.