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Exhibit 12.1


St. Mary Land & Exploration Company

Ratio of Earnings to Fixed Charges

(dollars in thousands)

 
   Three months ended March 31,
   Years ended December 31,
  
 
   2007
   2006
   2006
   2005
   2004
   2003
   2002
  
 
   Historical
   Pro forma(1)
    
   Historical
   Pro forma(1)
    
    
    
    
  
Pretax income from continuing operations   63,562   64,914   80,130   295,321   295,539   238,237   146,228   146,070 (2) 42,579  
Plus:                                      
Amortization of capitalized interest   416   416   215   1,022   1,022   745   507   393   247  
Fixed charges:                                      
Interest expense (includes amortization of deferred financing costs)   6,053   3,911   1,379   8,521   8,143   8,213   6,244   7,958   3,868  
Capitalized interest   1,327   1,327   682   3,465   3,465   1,909   1,353   780   427  
Interest factor in rental expense   173   173   140   612   612   546   610   509   424  
   
 
 
 
 
 
 
 
 
 
Total fixed charges   7,553   5,411   2,201   12,598   12,220   10,668   8,207   9,247   4,719  
Less:                                      
Capitalized interest   (1,327 ) (1,327 ) (682 ) (3,465 ) (3,465 ) (1,909 ) (1,353 ) (780 ) (427 )
Earnings   70,204   69,414   81,864   305,476   305,316   247,741   153,589   154,930   47,118  
Ratio of earnings to fixed charges   9.3   12.8   37.2   24.2   25.0   23.2   18.7   16.8   10.0  

Note:    For purposes of computing St. Mary Land & Exploration Company's ratios of earnings to fixed charges, "earnings" represent pretax income from continuing operations plus fixed charges and amortization of capitalized interest less 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 the pro forma effect of the use of net proceeds from the issuance in April 2007 of $287.5 million total principal amount of 3.50% senior convertible notes due 2027 to repay $280.8 million of debt under St. Mary's revolving credit facility.

(2)
Excludes cumulative effect of change in accounting principle, net of income tax, of approximately $5.4 million.



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St. Mary Land & Exploration Company Ratio of Earnings to Fixed Charges (dollars in thousands)