WASHINGTON • Average long-term U.S. mortgage rates ticked down modestly this week after six straight weeks of gains pushed rates to heights not seen in more than a decade.

Mortgage buyer Freddie Mac reported Thursday that the average on the key 30-year rate dipped to 6.66% from 6.70% last week. One year ago, the rate stood at 2.99%.

The average rate on 15-year, fixedrate mortgages, popular among those looking to refinance their homes, came down to 5.9% from 5.96% last week.

Rapidly rising mortgage rates have more than doubled this year, pushing many prospective homebuyers out of the market.

Freddie Mac says that for a typical mortgage, borrowers who locked in at the higher end of the rate range during the past year would pay several hundred dollars more than borrowers who signed contracts at the lower end of the range.

Late last month, the Federal Reserve bumped its benchmark borrowing rate by another three-quarters of a point

in an effort to constrain the economy, its fifth increase this year and third consecutive 0.75 percentage point increase.

The Fed’s aggressive action has decelerated a housing sector that — outside of the onset of the pandemic — has been hot for years. Existing home sales have declined for seven straight months as the rising cost to borrow money puts homes out of reach for more people.

The government reported last week that the U.S. economy, battered by surging consumer prices and rising interest rates, shrank at a 0.6% annual rate from April through June, consistent with its previous estimate for the second quarter.

Fed officials forecast that they will further raise their benchmark rate to roughly 4.4% by year’s end, a full point higher than they envisioned as recently as June.

They expect to raise the rate again next year, to about 4.6%.