Security Group 1 PSA Prepayment Assumption Rates Class Z Distribution Date 0% 100% 400% 500% 800% Initial Percent ..................    100 100 100 100 100 February 2003 ..................    106 106 106 106 106 February 2004 ..................    113 113 113 113 0 February 2005 ..................    120 120 120 120 0 February 2006 ..................    127 127 127 69 0 February 2007 ..................    135 135 135 1 0 February 2008 ..................    143 143 143 0 0 February 2009 ..................    152 152 152 0 0 February 2010 ..................    161 161 161 0 0 February 2011 ..................    171 171 171 0 0 February 2012 ..................    182 182 150 0 0 February 2013 ..................    193 193 117 0 0 February 2014 ..................    205 205 90 0 0 February 2015 ..................    218 218 68 0 0 February 2016 ..................    231 231 51 0 0 February 2017 ..................    245 245 38 0 0 February 2018 ..................    261 261 27 0 0 February 2019 ..................    277 277 20 0 0 February 2020 ..................    294 294 14 0 0 February 2021 ..................    312 312 9 0 0 February 2022 ..................    331 331 6 0 0 February 2023 ..................    351 351 4 0 0 February 2024 ..................    373 296 2 0 0 February 2025 ..................    396 181 1 0 0 February 2026 ..................    421 71 0 0 0 February 2027 ..................    446 0 0 0 0 February 2028 ..................    474 0 0 0 0 February 2029 ..................    503 0 0 0 0 February 2030 ..................    534 0 0 0 0 February 2031 ..................    439 0 0 0 0 February 2032 .................. 0 0 0 0 0 Weighted Average Life (years)  ..................  29.4 23.1 12.9 4.2 1.4 Security Group 2 PSA Prepayment Assumption Rates Classes D, FD and SD Distribution Date 0% 200% 406% 600% 825% Initial Percent ..................    100 100 100 100 100 February 2003 .................. 99 87 75 63 50 February 2004 .................. 98 75 56 40 25 February 2005 .................. 98 65 41 25 12 February 2006 .................. 97 56 31 16 6 February 2007 .................. 95 49 23 10 3 February 2008 .................. 94 42 17 6 1 February 2009 .................. 93 36 12 4 1 February 2010 .................. 92 31 9 2 0 February 2011 .................. 90 26 7 1 0 February 2012 .................. 89 22 5 1 0 February 2013 .................. 87 19 4 1 0 February 2014 .................. 85 16 3 0 0 February 2015 .................. 83 13 2 0 0 February 2016 .................. 81 11 1 0 0 February 2017 .................. 78 9 1 0 0 February 2018 .................. 75 7 1 0 0 February 2019 .................. 72 6 0 0 0 February 2020 .................. 69 5 0 0 0 February 2021 .................. 66 4 0 0 0 February 2022 .................. 62 3 0 0 0 February 2023 .................. 58 2 0 0 0 February 2024 .................. 53 1 0 0 0 February 2025 .................. 49 1 0 0 0 February 2026 .................. 43 0 0 0 0 February 2027 .................. 37 0 0 0 0 February 2028 .................. 31 0 0 0 0 February 2029 .................. 24 0 0 0 0 February 2030 .................. 17 0 0 0 0 February 2031 .................. 9 0 0 0 0 February 2032 .................. 0 0 0 0 0 Weighted Average Life (years)  ..................  20.8 6.4 3.4 2.2 1.5 S-19