Federal Cost of Funds Index
The Federal Cost of Funds Index (COFI) is used as a benchmark for some types of mortgage loans and securities. It is calculated as the sum of the monthly average interest rates for marketable Treasury bills and for marketable Treasury notes, divided by two, and rounded to three decimal places.
The Federal COFI is made available by Freddie Mac on or about the 20th day of each month. Freddie Mac first began publicly providing the Federal COFI in March, 1991; values are calculated for earlier years to illustrate what the index values would have been for those periods and are provided for research purposes only. The Federal COFI is not adjusted to reflect subsequent changes in the underlying Treasury rates once the value has been posted.
Posted on September 20, 2023; Latest data is 3.698% for August, 2023.