Exhibit 12.1

COMPUTATION OF RATIOS OF EARNINGS TO FIXED CHARGES

The
following table sets forth our ratios of earnings to fixed charges for the periods presented (amounts in thousands).



|                                                 |  |                         |         |  |      |   |         |      |  |   |         |   |  |      |        |   |  |   |        |  
|------------------------------------------------ |  | ----------------------- | ------- |  | ---- | - | ------- | ---- |  | - | ------- | - |  | ---- | ------ | - |  | - | ------ | -
|                                                 |  | Year ended December 31, |        
|                                                 |  | 2012                    |         |  | 2011 |   |         | 2010 |  |   | 2009    |   |  | 2008 |       
|Earnings:                                        |  |                         |         |  |      |   |         |      |  |   |         |   |  |      |        |   |  |   |        |  
|Earnings before income taxes                     |  | $                       | 805,312 |  |      | $ | 242,671 |      |  | $ | (44,357 | ) |  | $    | (6,100 | ) |  | $ | (6,064 | )
|                                                 |  |                         |         |  |     
|add:                                             |  |                         |         |  |      |   |         |      |  |   |         |   |  |      |        |   |  |   |        |  
|Fixed Charges                                    |  |                         | 122,535 |  |      |   | 88,278  |      |  |   | 1,777   |   |  |      | 74     |   |  |   | 45     |  
|                                                 |  |                         |         |  |      |   |         |      |  |   |         |   |  |      |        |   |  |   |        |  
|Adjusted Earnings                                |  | $                       | 927,847 |  |      | $ | 330,949 |      |  | $ | (42,580 | ) |  | $    | (6,026 | ) |  | $ | (6,019 | )
|                                                 |  |                         |         |  |      |   |         |      |  |   |         |   |  |      |        |   |  |   |        |  
|Fixed Charges:                                   |  |                         |         |  |      |   |         |      |  |   |         |   |  |      |        |   |  |   |        |  
|Interest Expense (includes capitalized interest) |  |                         | 105,710 |  |      |   | 88,484  |      |  |   | 1,354   |   |  |      |       |   |  |   |       |  
|Amortization of debt discount and expense        |  |                         | 9,806   |  |      |   | 3,174   |      |  |   | 67      |   |  |      |       |   |  |   |       |  
|Estimate of interest within rental expense       |  |                         | 13,716  |  |      |   | 9,647   |      |  |   | 356     |   |  |      | 74     |   |  |   | 45     |  
|                                                 |  |                         |         |  |      |   |         |      |  |   |         |   |  |      |        |   |  |   |        |  
|Fixed Charges                                    |  | $                       | 129,232 |  |      | $ | 101,305 |      |  | $ | 1,777   |   |  | $    | 74     |   |  | $ | 45     |  
|                                                 |  |                         |         |  |      |   |         |      |  |   |         |   |  |      |        |   |  |   |        |  
|                                                 |  |                         |         |  |     
|Ratio of Earnings to Fixed Charges (a)           |  |                         | 7.2x    |  |      |   | 3.3x    |      |  |   |        |   |  |      |       |   |  |   |       |  
|                                                 |  |                         |         |  |     
|Coverage deficiency (b)                          |  |                         |        |  |      |   |        |      |  | $ | 42,580  |   |  | $    | 6,026  |   |  | $ | 6,019  |  



|(a) | For purposes of determining the ratio of earnings to fixed charges, earnings consist of income from continuing operations before income taxes and fixed charges
(excluding interest capitalized during the period). Fixed charges consist of interest expense (including interest capitalized during the period), amortization of debt discount and deferred financing costs and the portion of rental expense that is
representative of the interest factor in these rentals.
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|(b) | The earnings for the years ended December 31, 2008, 2009 and 2010 were inadequate to cover fixed charges.
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