WASHINGTON — Rates on 30-year mortgages were unchanged this week while rates on other types of mortgages also showed little movement.

Freddie Mac, the mortgage company, reported yesterday that 30-year fixed-rate mortgages averaged 6.40 percent this week, the same as last week.

The nationwide average for 30-year mortgages had dipped in mid-September to 6.31 percent, the lowest level since mid-May, but have generally been trending higher since that time.

Analysts attributed the flat pattern for rates this week to mixed economic reports.

Treasury Secretary Henry Paulson and Federal Reserve Chairman Ben Bernanke warned on Monday that the severe slump in housing is likely to last longer than expected.

The Fed cut interest rates for the first time in four years at its September meeting, and economists believe the central bank could cut rates again at its next meeting on Oct. 30-31 if the economic data weakens further. The Commerce Department reported this week that construction of new homes fell to a 14-year low in September.

Rates on 15-year fixed-rate mortgages, a popular choice for refinancing, averaged 6.08 percent this week, up only slightly from 6.06 percent last week.

Rates on five-year adjustable-rate mortgages averaged 6.11 percent, basically unchanged from 6.12 percent the previous week.

Rates on one-year ARMs edged up to 5.76 percent, compared to 5.73 percent last week.