Base Offering Circular – Multifamily 11 index only if it receives an Opinion of Counsel that the selection of that index will not cause the related Trust REMIC or Trust REMICs to lose their status as REMICs for federal income tax purposes. If at any time after the occurrence of an Alternative Rate Event, the FHLB of San Francisco resumes publication of COFI, the Interest Rates of the COFI Classes for each subsequent Accrual Period will be calculated by reference to COFI. Determination of the Treasury Index Unless otherwise provided in the applicable Offering Circular Supplement, the Trustee (or its agent) will calculate the Interest Rates of Treasury Index Classes for each Accrual Period (after the first) on the Floating Rate Adjustment Date. On each Floating Rate Adjustment Date, the Trustee will determine the applicable Treasury Index, which will be either (i) the weekly average yield, expressed as a per annum rate, on U.S. Treasury securities adjusted to a constant maturity of one, three, five, seven or ten years or to some other constant maturity (as specified in the applicable Offering Circular Supplement) as published by the Federal Reserve Board in the most recent edition of Federal Reserve Board Statistical Release No. H.15 (519) that is available to the Trustee or (ii) the weekly auction average (investment) yield, expressed as a per annum rate, on three-month or six-month U.S. Treasury bills that is available on the Treasury Public Affairs Information Line, an automated telephone system. The Statistical Release No. H.15 (519) is published by the Federal Reserve on Monday or Tuesday of each week. Investors can order it from the Publications Department at the Board of Governors of the Federal Reserve System, 21st and C Streets, N.W., M.S. 138, Washington, D.C. 20551. The Trustee will consider a new value for the Treasury Index to have been available on the day following the date that Statistical Release No. H.15 (519) is released by the Federal Reserve Board or the Public Debt News is placed on the Treasury Public Affairs Public Information Line and available to the public. The applicable auction average (investment) yield for a given week is the yield resulting from the auction of three-month or six-month U.S. Treasury bills held the preceding week. The weekly average yield reflects the average yields of the five calendar days ending on Friday of the previous week. Yields on Treasury securities at “constant maturity” are estimated from the Treasury’s daily yield curve. This curve, which relates the yield on a security to its time to maturity, is based on the closing market bid yields on actively traded Treasury securities in the over-the-counter market. These market yields are calculated from composites of quotations reported by five leading U.S. Government securities dealers to the Federal Reserve Bank of New York. This method permits estimation of the yield for a given maturity even if no security with that exact maturity is outstanding. In the event that the applicable Treasury Index becomes unavailable, the Trustee (or its agent) will designate a new index, approved by Ginnie Mae, based upon comparable information and methodology. The Trustee will select a particular index as the alternative index only if it receives an Opinion of Counsel that the selection of the alternative index will not cause the related Trust REMIC or Trust REMICs to lose their status as REMICs for federal income tax purposes.