Exhibit A Underlying Certificates Issuer Series Class Issue Date CUSIP Number Interest Rate Interest Type(1) Final Group 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 2 Ginnie Mae  2007-044  CA(3)  July 30, 2007  38375KD74 6.00% FIX October 2036 SUP $37,500,000 0.94192205 $30,751,297 87.0597093333% 6.483% 343 15 II 2 Ginnie Mae  2007-044  CB(3)  July 30, 2007  38375KD66 6.00% FIX July 2037 SUP 12,551,809 1.00000000 10,927,568 87.0597058958% 6.483% 343 15 II (1)  As defined under "Class Types" in Appendix I to the Base Offering Circular. (2)  Underlying Certificate Factors are as of October 2007. (3)  MX Class. A-1