Exhibit B Underlying Certificates Issuer Series Class Issue Date CUSIP Number Interest Rate Interest Type(1) Final Distribution Date Principal Type(1) Original Principal Balance of Class Underlying Certificate Factor(2) Principal Balance in Trust Percentage of Class in Trust Approximate Weighted Average Coupon of Mortgage Loans Approximate Weighted Average Remaining Term to Maturity of Mortgage Loans (in months) Approximate Weighted Average Loan Age of Mortgage Loans (in months) Ginnie Mae I or II Ginnie Mae 2002-35 D May 30, 2002 38373MBZ2 (3) WAC/DLY January 2027 SEQ $  63,344,000 1.00000000 $20,000,000 31.5736297045% 6.939% 350 67 I Ginnie Mae 2003-064 E August 29, 2003 38374BSV6 (3) WAC/DLY April 2039 SEQ 119,184,090 1.00000000 22,000,000 18.4588395985 6.041 388 51 I Ginnie Mae 2006-008 A March 30, 2006 38373MTK6 3.942% FIX August 2025 SEQ 141,538,495 0.89642560 17,928,512 14.1304314420 5.951 415 24 I Ginnie Mae 2006-046 B August 30, 2006 38373MVP2 (3) WAC/DLY June 2034 SEQ 54,543,000 1.00000000 10,000,000 18.3341583705 6.068 401 23 I Ginnie Mae 2007-012 A March 30, 2007 38373MYF1 3.957 FIX June 2031 SEQ 176,375,000 0.98899518 30,337,427 17.3919206237 5.863 399 11 I (1)  As defined under "Class Types" in Appendix I to the Base Offering Circular. (2)  Underlying Certificates Factors as of June 2007. (3)  These Underlying Certificates bear interest during their interest accrual periods as further described in the related Underlying Certificate Disclosure Documents, excerpts of which are attached as Exhibit C to this Supplement. B-1