The cost of funds index rose again -- this time to a new four-year high.

COFI, as it is widely known, was 3.074% in October, according to the Federal Home Loan Bank of San Francisco. The index is 10 basis points higher than the prior month and 111 BPS higher than October 2004.

The index has risen every month since May 2004.

The last time COFI was this high was December 2001 -- when it was also reported at 3.074%. However, at that time, as rates were still tumbling, the COFI was at its lowest point in decades.

The index, reported about 30 days following the end of each month, is based on the interest expense of member banks headquartered in Arizona, California, and Nevada. For the latest period, average total funds used in the calculation were $577.6 billion.

Another competing index for adjustable-rate mortgages, the 6-month London Interbank Offer Rate, rose to 4.5795% in November from October's 4.4467%, Fannie Mae reported. A year ago, the LIBOR stood at 2.6239%.

The LIBOR has reportedly increased each consecutive month since April 2004 and is currently at the highest level since March 2001 when it was 4.711%.