The cost of funds index tumbled nearly 15 basis points in September to its lowest level on record.
The Federal Home Loan Bank of San Francisco reported Friday that COFI was 1.272% in September. The index was down from 1.412% in August and 2.769% in September 2008.
COFI has never been this low based on FHLB data dating back to July 1981 — the oldest available data — when the COFI sat at 11.848%.
The index, used on many negatively amortizing adjustable-rate mortgages, is calculated based on the interest expense of FHLB-member institutions headquartered in Arizona, California and Nevada. During September, average total funds used in the calculation were $89.4 billion, down from August’s $90.3 billion.
A more widely used ARM index is the yield on the one-year Treasury bill, which fell to 0.40% at the end of September from 0.43% at the end of August, based on U.S. Department of the Treasury data. The one-year Treasury bill yield closed Friday at 0.37%.
The yield on the six-month London Interbank Offered Rate, a popular index on subprime ARMs, ended September at 0.63%, tumbling from 0.79% at the end of August. LIBOR finished October at 0.58%.
ARMs accounted for 6.9% of loan applications tracked in the Mortgage Bankers Association’s Weekly Mortgage Applications Survey for the week ended Oct. 23.
