The average interest on a 30-year mortgage fell to a 38-year low of 4.85 percent during the week ending March 27 from 4.98 percent the prior week, Freddie Mac reported.

The decrease came on the heels of the Federal Reserve’s announcement that it plans to purchase another $750 billion in mortgage-backed securities and up to $300 million in Treasuries. President Obama says refinancing is now possible for 40 percent of mortgages and encourages home owners to reap the benefits of the record-low rates.