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News Summary: 30-year mortgage rate at 3.40 pct.

WASHINGTON (AP) -- RATES FALL: The average U.S. rate on the 30-year mortgage fell closer this week to a historic low and the 15-year rate marked a new record low. Low rates are increasing the affordability of buying homes and refinancing.

THE NUMBERS: The average rate on the 30-year loan slipped to 3.40 percent from 3.41 percent last week. That's near the 3.31 percent rate reached in November, which was the lowest on records dating to 1971. The average rate on the 15-year mortgage fell to 2.61 percent from 2.64 percent. That's below the previous record low of 2.63 percent in November, the lowest since 1991.

HOUSING RECOVERY: Low mortgage rates are helping drive a housing recovery that began last year. Home prices are rising. Sales of new and previously occupied homes are up this year.