Security Group 2 PSA Prepayment Assumption Rates Class DA Class DZ Distribution Date 0% 100% 228% 350% 500% 0% 100% 228% 350% 500% Initial Percent ..................    100 100 100 100 100 100 100 100 100 100 April 2005.......................... 93 90 87 83 79 105 105 105 105 105 April 2006.......................... 85 77 68 59 49 109 109 109 109 109 April 2007.......................... 77 63 47 34 20 114 114 114 114 114 April 2008.......................... 68 50 30 15 0 120 120 120 120 118 April 2009.......................... 60 37 15 0 0 125 125 125 124 77 April 2010.......................... 50 25 3 0 0 131 131 131 90 49 April 2011.......................... 40 14 0 0 0 137 137 110 64 31 April 2012.......................... 30 3 0 0 0 143 143 84 45 19 April 2013.......................... 19 0 0 0 0 150 126 63 31 12 April 2014.......................... 8 0 0 0 0 157 100 46 21 7 April 2015.......................... 0 0 0 0 0 150 75 32 13 4 April 2016.......................... 0 0 0 0 0 115 53 21 8 2 April 2017.......................... 0 0 0 0 0 79 32 11 4 1 April 2018.......................... 0 0 0 0 0 40 12 4 1 0 April 2019.......................... 0 0 0 0 0 0 0 0 0 0 Weighted Average Life (years)  .................. 5.8 4.1 3.0 2.4 2.0 12.9 11.2 9.3 7.7 6.2 Security Group 3 PSA Prepayment Assumption Rates Classes F and S Class LA Distribution Date 0% 150% 285% 450% 600% 0% 150% 285% 450% 600% Initial Percent ..................    100 100 100 100 100 100 100 100 100 100 April 2005.......................... 99 96 96 96 96 100 95 69 36 6 April 2006.......................... 97 89 89 80 72 100 84 0 0 0 April 2007.......................... 96 81 73 58 46 100 71 0 0 0 April 2008.......................... 94 73 60 42 29 100 60 0 0 0 April 2009.......................... 92 65 49 30 18 100 52 0 0 0 April 2010.......................... 91 58 40 21 11 100 46 0 0 0 April 2011.......................... 89 52 32 15 7 100 41 0 0 0 April 2012.......................... 87 46 26 11 4 100 38 0 0 0 April 2013.......................... 84 40 21 8 3 100 37 0 0 0 April 2014.......................... 82 36 17 6 2 100 36 0 0 0 April 2015.......................... 80 31 14 4 1 100 35 0 0 0 April 2016.......................... 77 27 11 3 1 100 34 0 0 0 April 2017.......................... 74 24 9 2 0 100 32 0 0 0 April 2018.......................... 71 20 7 1 0 100 30 0 0 0 April 2019.......................... 68 18 6 1 0 100 28 0 0 0 April 2020.......................... 65 15 4 1 0 100 26 0 0 0 April 2021.......................... 62 13 3 0 0 100 24 0 0 0 April 2022.......................... 58 11 3 0 0 100 22 0 0 0 April 2023.......................... 54 9 2 0 0 100 19 0 0 0 April 2024.......................... 50 8 2 0 0 100 17 0 0 0 April 2025.......................... 45 6 1 0 0 100 15 0 0 0 April 2026.......................... 41 5 1 0 0 100 13 0 0 0 April 2027.......................... 35 4 1 0 0 100 11 0 0 0 April 2028.......................... 30 3 0 0 0 100 9 0 0 0 April 2029.......................... 25 2 0 0 0 100 7 0 0 0 April 2030.......................... 19 2 0 0 0 100 5 0 0 0 April 2031.......................... 12 1 0 0 0 100 3 0 0 0 April 2032.......................... 5 1 0 0 0 100 2 0 0 0 April 2033.......................... 0 0 0 0 0 81 0 0 0 0 April 2034.......................... 0 0 0 0 0 0 0 0 0 0 Weighted Average Life (years)  ..................   18.3 8.9 6.2 4.3 3.4 29.4 9.4 1.3 0.8 0.6 S-21