May 29, 2012 –The Federal Housing Finance Agency (FHFA)reported that the National Average Contract Mortgage Rate for the Purchase of Previously Occupied Homes by Combined Lenders, used as an index in some ARM contracts, was 3.93 percent based on loans closed in April. Beginning in March, FHFA is calculating interest rates using un-weighted survey data. There was an increase of 0.03 percent from the previous month. Read more.