30-YEAR BELOW 3.50: The average U.S. rate on the 30-year fixed mortgage fell below 3.50 percent for the first time on records dating back 60 years.

THE NUMBERS: The rate on the 30-year loan dipped to a record low of 3.49 percent, mortgage buyer Freddie Mac says. The rate on the 15-year mortgage declined to 2.80 percent, also a record.

OUTLOOK: Cheaper mortgages have helped drive a modest but uneven housing recovery this year.