Sensitivity of Class QE to Prepayments Assumed Price 98.09375%* PSA Prepayment Assumption Rates LIBOR 100% 225% 350% 500% 0.1% .......................................... 18.9% 19.0% 19.0% 19.1% 1.1% .......................................... 15.7% 15.7% 15.8% 15.9% 4.1% .......................................... 6.2% 6.3% 6.4% 6.5% 6.0% and above ...................... 0.3% 0.4% 0.5% 0.7% Sensitivity of Class UC to Prepayments Assumed Price 8.875%* PSA Prepayment Assumption Rates LIBOR 100% 225% 350% 500% 0.1%  .......................................... 67.4% 62.6% 59.6% 52.7% 1.1%  .......................................... 53.4% 48.4% 45.0% 37.7% 4.1%  .......................................... 12.5% 7.6% 2.5%   (6.4)% 6.0% and above ...................... ** ** ** ** Sensitivity of Class UD to Prepayments Assumed Price 3.75%* PSA Prepayment Assumption Rates LIBOR 100% 225% 350% 500% 6.0% and below ...................... 24.9% 19.8% 15.3% 6.9% 6.6%  .......................................... 5.3% 0.9% (4.5)%   (13.7)% 7.2% and above ...................... ** ** ** ** SECURITY GROUP 6 Sensitivity of Class QX to Prepayments Assumed Price 11.75%* PSA Prepayment Assumption Rates LIBOR 125% 251% 400% 550% 0.10% ........................................ 61.2% 50.5% 37.1% 22.6% 1.10% ........................................ 51.0% 40.7% 27.7% 13.6% 4.10% ........................................ 21.6% 12.2% 0.0%   (13.5)% 7.25% and above ....................   (14.3)%   (23.9)%   (37.6)%   (53.2)% *  The price does not include accrued interest. Accrued interest has been added to the price in calculating the yields set forth in the table. **  Indicates that investors will suffer a loss of virtually all of their investment. S-42