The average rate on a 30-year mortgage in the U.S. climbed to its highest level in eight weeks, a setback for home shoppers in the midst of the spring homebuying season.

The rate rose to 6.83% from 6.62% last week, mortgage buyer Freddie Mac said Thursday. A year ago, the rate averaged 7.1%.

Borrowing costs on 15-year fixed-rate mortgages, popular with homeowners refinancing their home loans, also rose. The average rate increased to 6.03% from 5.82% last week. It’s still down from 6.39% a year ago, Freddie Mac said.

Mortgage rates are influenced by several factors, including global demand for U.S. Treasurys, the Federal Reserve’s interest rate policy decisions and bond market investors’ expectations for future inflation.

The average rate on a 30-year mortgage loosely follows moves in the 10-year Treasury yield, which lenders use as a guide to pricing home loans.

The yield, which had mostly fallen this year after climbing to around 4.8% in mid-January, spiked last week to 4.5% amid a sell-off in government bonds triggered by investor anxiety over the potential fallout from the Trump administration’s escalating tariff war.

The 10-year Treasury yield was at 4.32% in midday trading Thursday.