WASHINGTON — Rates on 30-year mortgages climbed this week to their highest point in nearly four years, helping take the exuberance out of the housing market.

Freddie Mac, the mortgage company, reported yesterday that for the week ending May 18, rates on 30-year, fixed-rate mortgages averaged 6.60 percent, up from 6.58 percent last week.

This week's rate was the highest since the week ending June 20, 2002, when 30-year mortgages stood at 6.63 percent.

"While financial markets try to decipher the spate of recently released economic reports, mortgage rates drifted slightly higher," said Frank Nothaft, chief economist at the Federal Home Mortgage Loan Corp. or Freddie Mac. "The current debate is between rising inflation and slower consumer spending. Until the market finds out which influence will be the strongest, mortgage rates should continue to fluctuate."

Other rates also went up this week.

Rates on 15-year, fixed-rate mortgages, a popular choice for refinancing a home mortgage, rose to 6.20 percent, up from 6.17 percent last week. For five-year, hybrid adjustable-rate mortgages, rates edged up to 6.23 percent this week, compared with 6.22 percent last week.

However, rates for one-year adjustable rate mortgages averaged 5.62 percent this week, unchanged from last week.

Higher mortgage rates are slowing home sales. For five years in a row, home sales hit record highs as low mortgage rates beckoned buyers.

Federal Reserve Chairman Ben Bernanke, speaking in Chicago yesterday, noted the slowing in both home sales and residential construction. "It seems pretty clear now that the U.S. housing market is cooling," he said.

"Our assessment at this point ... is that this looks to be a very orderly and moderate kind of cooling."

The mortgage rates do not include add-on fees known as points. The one-year ARM carried a nationwide average fee of 0.7 point; the other three mortgage categories each had an average fee of 0.5 point.

A year ago, 30-year mortgages averaged 5.71 percent, 15-year mortgages stood at 5.27 percent, one-year ARMs were at 4.26 percent and five-year ARMs averaged 5.07 percent.