Exhibit 12.1

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES



|                                              |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        
|--------------------------------------------- |  | --------------------------------- | ------- | ------------------------ | - | -------- | ------------------------ |  | ------------------------ | ------- | ------------------------ | - | ------------------------ |  | - | ------ |  | - | -------
|(in thousands of U.S. dollars, except ratios) |  | Nine MonthsEndedSeptember 30,2009 |         | Year EndDecember 31,2008 |   |          | Year EndDecember 31,2007 |  | Year EndDecember 31,2006 |         | Year EndDecember 31,2005 |   | Year EndDecember 31,2004
|Earnings:                                     |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        
|Pre-tax income (loss)                         |  | $                                 | 188,635 |                          | $ | (174,086 | )                        |  | $                        | 302,827 |                          | $ | 217,988                  |  | $ | 10,477 |  | $ | 141,754
|Fixed charges                                 |  |                                   | 16,021  |                          |   | 37,462   |                          |  |                          | 43,562  |                          |   | 14,503                   |  |   | 23,235 |  |   | 21,190 
|                                              |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        
|Total Earnings (Loss)                         |  | $                                 | 204,656 |                          | $ | (136,624 | )                        |  | $                        | 346,389 |                          | $ | 232,491                  |  | $ | 33,712 |  | $ | 162,944
|                                              |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        
|Fixed Charges:                                |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        
|Interest and amortization on indebtedness     |  | $                                 | 14,741  |                          | $ | 36,143   |                          |  | $                        | 42,702  |                          | $ | 13,832                   |  | $ | 22,764 |  | $ | 20,644 
|Rental expense at 33.3% (1)                   |  |                                   | 1,280   |                          |   | 1,319    |                          |  |                          | 860     |                          |   | 671                      |  |   | 471    |  |   | 546    
|                                              |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        
|Total Fixed Charges                           |  | $                                 | 16,021  |                          | $ | 37,462   |                          |  | $                        | 43,562  |                          | $ | 14,503                   |  | $ | 23,235 |  | $ | 21,190 
|                                              |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        
|Ratio of Earnings to Fixed Charges            |  |                                   | 12.77   |                          |   | (3.7     | )                        |  |                          | 8.0     |                          |   | 16.0                     |  |   | 1.5    |  |   | 7.7    
|                                              |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        
|Deficiency                                    |  |                                   | N/A     |                          | $ | 174,086  |                          |  |                          | N/A     |                          |   | N/A                      |  |   | N/A    |  |   | N/A    
|                                              |  |                                   |         |                          |   |          |                          |  |                          |         |                          |   |                          |  |   |        |  |   |        



|(1) | 33.3% represents a reasonable approximation of the interest factor
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