LOS ANGELES (AP) — The average long-term U.S. mortgage rate climbed this week to its highest level since late November, another setback for home shoppers in what’s traditionally the housing market’s busiest time of the year.

The average rate on a 30-year mortgage rose to 7.17% from 7.1% last week, mortgage buyer Freddie Mac said Thursday. A year ago, the rate averaged 6.43%.

Borrowing costs on 15-year fixed-rate mortgages, popular with homeowners refinancing their home loans, also rose this week, lifting the average rate to 6.44% from 6.39% last week. A year ago, it averaged 5.71%, Freddie Mac said.

When mortgage rates rise, they can add hundreds of dollars a month in costs for borrowers, limiting how much they can afford at a time when the U.S. housing market remains constrained by relatively few homes for sale and rising home prices.