Exhibit 12.1



RATIO OF EARNINGS TO FIXED CHARGES

The ratio of earnings to fixed charges for the periods shown
has been computed by dividing earnings available for fixed charges (income from
continuing operations before income taxes plus fixed charges including
capitalized interest) by fixed charges (interest expense including capitalized
interest). Interest expense includes the portion of operating rental expense,
which we believe is representative of the interest component of rental expense.

|                                                            |  |                                |                                         |  |      |   |         |      |  |      |         |      |   |        |  |   |        | 
|----------------------------------------------------------- |  | ------------------------------ | --------------------------------------- |  | ---- | - | ------- | ---- |  | ---- | ------- | ---- | - | ------ |  | - | ------ | 
|                                                            |  | Years
      Ended December 31, |                                        
|                                                            |  | 2005                           |                                         |  | 2004 |   |         | 2003 |  | 2002 |         | 2001 |  
|                                                            |  |                                | (In
      thousands, except ratio data)
|Income from continuing operations before income
      taxes |  | $                              | 181,725                                 |  |      | $ | 193,664 |      |  | $    | 131,477 |      | $ | 77,430 |  | $ | 1,616  | 
|                                                            |  |                                |                                         |  |      |   |         |      |  |      |         |      |   |        |  |   |        | 
|Fixed Charges:                                              |  |                                |                                        
|Interest expense (including capitalized interest)(1)        |  |                                | 8,791                                   |  |      |   | 4,698   |      |  |      | 5,506   |      |   | 7,700  |  |   | 18,304 | 
|Interest relating to rental expense (2)                     |  |                                | 6,603                                   |  |      |   | 7,695   |      |  |      | 6,795   |      |   | 5,205  |  |   | 2,682  | 
|                                                            |  |                                |                                         |  |      |   |         |      |  |      |         |      |   |        |  |   |        | 
|Total Fixed Charges                                         |  |                                | 15,394                                  |  |      |   | 12,393  |      |  |      | 12,301  |      |   | 12,905 |  |   | 20,986 | 
|                                                            |  |                                |                                         |  |      |   |         |      |  |      |         |      |   |        |  |   |        | 
|Earnings Available For Fixed Charges                        |  | $                              | 197,119                                 |  |      | $ | 206,057 |      |  | $    | 143,778 |      | $ | 90,335 |  | $ | 22,602 | 
|                                                            |  |                                |                                         |  |      |   |         |      |  |      |         |      |   |        |  |   |        | 
|Ratio Of Earnings To Fixed Charges                          |  |                                | 12.80                                   |  |      |   | 16.63   |      |  |      | 11.69   |      |   | 7.00   |  |   | 1.08   | 



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|(1) | Included in this amount
      is $1.5 million in prepaid interest and $1.2 million of deferred costs
      associated with the induced conversion of $63.0millionin senior convertible
      debentures in 2005.
|--- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|(2) | The representative
      interest portion of rental expense was deemed to be one-third of all
      rental expense.