| Purchases summarize all trades executed during the indicated period including purchases associated with dollar rolls.* | 
             
                   
                  
                     
                      | Transactions 
                        ($ million) | 
                     
                    
                     
                       
                           
                            Maturity  | 
                            Coupon  | 
                            Settlement 
                                Month  | 
                            FHLMC  | 
                            FNMA  | 
                            GNMA  | 
                            GNMA2  | 
                           
                          
                            30 Year  | 
                            3.5 | 
                            Sep | 
                            0 | 
                            0 | 
                            0 | 
                            365 | 
                             
                          
                            |   | 
                            3.5 | 
                            Oct | 
                            862 | 
                            1,177 | 
                            0 | 
                            1,066 | 
                             
                          
                            |   | 
                            4 | 
                            Sep | 
                            0 | 
                            200 | 
                            0 | 
                            314 | 
                           
                          
                            |   | 
                            4 | 
                            Oct | 
                            1,154 | 
                            1,492 | 
                            0 | 
                            958 | 
                           
                          
                            |   | 
                              | 
                              | 
                              | 
                              | 
                              | 
                              | 
                           
                          
                            15 Year  | 
                            3 | 
                            Oct | 
                            52 | 
                            78 | 
                            0 | 
                            0 | 
                                       
                          
                            |   | 
                            3.5 | 
                            Oct | 
                            52 | 
                            100 | 
                            0 | 
                            0 | 
                                           
                          
                            |   | 
                               | 
                               | 
                               | 
                               | 
                               | 
                               | 
                                                                                  
                           
                            | Total | 
                              | 
                              | 
                            2,120 | 
                            3,047 | 
                            0 | 
                            2,703 | 
                           
                          
                          	*Does not include trades associated with small value exercises.  | 
                           
                        | 
                     
                   
                  
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