LIBOR decreases below that level, the Effective Rate for Class FC may change or cease to exist
and its Weighted Average Life may be extended, perhaps significantly. Moreover, the Mortgage
Loans will not prepay at any constant rate. Non-constant prepayment rates can cause any PAC or
TAC Class not to receive Scheduled Payments, even if prepayment rates remain within the
initial Effective Range (or if prepayment rates average the Effective Rate), if any, for that Class.
Further, the Effective Range for any PAC Class can narrow, shift over time or cease to exist and
the Effective Rate for the TAC Class can change or cease to exist depending on the actual
characteristics of the Mortgage Loans.
If the related Mortgage Loans prepay at rates that are generally below the Effective Range or
Rate for any PAC or TAC Class, the amount available to pay principal on the Securities may be
insufficient to produce Scheduled Payments on such related PAC or TAC Class, if any, and its
Weighted Average Life may be extended, perhaps significantly.
If the related Mortgage Loans prepay at rates that are generally above the Effective Range or
Rate for any PAC or TAC Class, its supporting Classes may be retired earlier than that PAC or
TAC Class, and its Weighted Average Life may be shortened, perhaps significantly.
Assumability
Each Mortgage Loan may be assumed, subject to HUD review and approval, upon the sale
of the related Mortgaged Property. See "Yield, Maturity and Prepayment Considerations
Assumability of Government Loans" in the Base Offering Circular.
Final Distribution Date
The Final Distribution Date for each Class, which is set forth on the front cover of this
Supplement or on Schedule I to this Supplement, is the latest date on which the related
Class Principal Balance or Class Notional Balance will be reduced to zero.
The actual retirement of any Class may occur earlier than its Final Distribution Date.
According to the terms of the Ginnie Mae Guaranty, Ginnie Mae will guarantee payment
in full of the Class Principal Balance of each Class of Securities no later than its Final
Distribution Date.
Modeling Assumptions
Unless otherwise indicated, the tables that follow have been prepared on the basis of the
following assumptions (the "Modeling Assumptions"), among others:
1. The Mortgage Loans underlying the Trust Assets have the assumed characteristics shown
under "Assumed Characteristics of the Mortgage Loans Underlying the Trust Assets" in the
Terms Sheet, except in the case of information set forth under the 0% PSA Prepayment
Assumption Rate, for which each Mortgage Loan underlying a Trust Asset is assumed to have an
original and a remaining term to maturity of 360 months and a Mortgage Rate of 1.50% per
annum higher than the related Certificate Rate.
2. The Mortgage Loans prepay at the constant percentages of PSA (described below)
shown in the related table.
3. Distributions on the Securities are always received on the 20th day of the month,
whether or not a Business Day, commencing in November 2007.
4. A termination of the Trust does not occur.
5. The Closing Date for the Securities is October 30, 2007.
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