WASHINGTON — Rates on 30-year mortgages fell this week after two consecutive increases, providing a break for potential home buyers and the beleaguered housing industry.

Freddie Mac, the mortgage company, reported yesterday that 30-year fixed-rate mortgages averaged 6.37 percent this week, down from 6.42 percent last week. After hitting a high for this year of 6.73 percent in mid-July, rates have been trending lower as the worst slump in housing in 16 years has contributed to slower economic growth and fewer worries about inflation.

Two weeks ago, the nationwide average for 30-year mortgages dipped to 6.31 percent, the lowest level since May 17. That decline reflected in part a flight to the safety of Treasury securities in August after a bout of turbulence in credit markets.

The Federal Reserve announced two weeks ago that it was cutting a key interest rate by a more-than-expected half-point in an effort to make sure that the housing slump and the most severe credit crunch in almost a decade don't push the economy into a recession.

In the 12 months ending in July, the housing sector lost 260,000 jobs, reflecting continued cutbacks in construction as builders scramble to trim record levels of unsold homes in the face of falling sales.

Rates on 15-year fixed-rate mortgages, a popular choice for refinancing, averaged 6.03 percent this week, down from 6.09 percent last week.

Rates on five-year adjustable rate mortgages averaged 6.11 percent, down from 6.15 percent last week. One-year ARMs averaged 5.58 percent, down from 5.60 percent.

A year ago, 30-year mortgages stood at 6.30 percent, 15-year mortgages at 5.98 percent and five-year ARMS at 6.00 percent.