The average rate on a 30-year mortgage in the U.S. edged higher this week, ending a seven-week slide that helped ease borrowing costs for home shoppers leading into the spring homebuying season.

The rate averaged 6.65% this week, up from 6.63% last week, mortgage buyer Freddie Mac said Thursday. A year ago, it averaged 6.74%.

Borrowing costs on 15-year fixed-rate mortgages, popular with homeowners seeking to refinance their home loan to a lower rate, also ticked up this week. The average rate rose to 5.8% from 5.79% last week. A year ago, it averaged 6.16%, Freddie Mac said.

Mortgage rates are influenced by several factors, including how the bond market reacts to the Federal Reserve’s interest rate policy decisions.

After climbing to just above 7% in mid-January, the average rate on a 30-year mortgage declined through last week, echoing moves in the 10-year Treasury yield, which lenders use as a guide to pricing home loans. So far, the pullback in rates hasn’t improved the affordability equation for many would-be homebuyers, keeping the housing market in a sales slump.