Exhibit 12

CREDIT SUISSE FIRST BOSTON (USA), INC.        STATEMENT RE COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES        (In thousands, except for ratio)

|                                                              |                                                 | For the Years Ended      |           | For the Six Months
Ended
June 30,
|------------------------------------------------------------- | ----------------------------------------------- | ------------------------ | --------- | ---------------------------------
|
|Earnings:                                                     |                                                 |                          |           |                                  
|                                                              | Income (loss) before provision for income taxes |                          | $         | 473,800                          
|Add: Fixed Charges Interest expense (gross)                   |                                                 |                          | 2,865,800 |                                  
|                                                              |                                                 | Interest factor in rents |           |                                  
|                                                              |                                                 |                          |           |                                  
|                                                              |                                                 | Total fixed charges      |           |                                  
|Earnings before fixed charges, and provision for income taxes |                                                 | $                        | 3,365,115 |                                  
|                                                              |                                                 |                          |           |                                  
|Ratio of earnings to fixed charges                            |                                                 |                          | 1.16      |                                  
|                                                              |                                                 |                          |           |                                  

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Exhibit 12.1

CREDIT SUISSE FIRST BOSTON (USA), INC.        STATEMENT RE COMPUTATION OF RATIO OF EARNINGS  TO FIXED CHARGES AND PREFERRED DIVIDENDS        (In thousands, except
for ratio)

|                                                             |                                                 | For the Years Ended |           | For the
Six Months
Ended
June 30,
|------------------------------------------------------------ | ----------------------------------------------- | ------------------- | --------- | ---------------------------------
|
|Earnings:                                                    |                                                 |                     |           |                                  
|                                                             | Income (loss) before provision for income taxes |                     | $         | 473,800                          
|Add: Fixed Charges                                           |                                                 |                     |           |                                  
|                                                             | Interest expense (gross)                        |                     |           | 2,865,800                        
|                                                             | Interest factor in rents                        |                     |           | 25,515                           
|                                                             |                                                 |                     |           |                                  
|                                                             | Total fixed charges                             |                     |           | 2,891,315                        
|Add: Preferred dividends                                     |                                                 |                     | 18,653    |                                  
|                                                             | Combined fixed charges and preferred dividends  |                     |           | 2,909,968                        
|Earnings before fixed charges and provision for income taxes |                                                 | $                   | 3,365,115 |                                  
|                                                             |                                                 |                     |           |                                  
|Ratio of earnings to fixed charges and preferred dividends   |                                                 |                     | 1.16      |                                  
|                                                             |                                                 |                     |           |                                  

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