WASHINGTON (AP) — Long-term U.S. mortgage rates were unchanged this week, leaving the average 30-year fixed mortgage rate at the lowest level this year.

Mortgage buyer Freddie Mac says the 30-year fixed mortgage rate was 3.78 percent. While the same as the previous week, that is down sharply from this year's peak of 4.3 percent, reached in March. It remains slightly above last year's average of 3.65 percent.

Long-term mortgage rates typically follow the yield on the 10-year Treasury note. The 10-year yield ticked up this week, Freddie Mac said, suggesting mortgage rates could pick up next week.

The 15-year mortgage stayed 3.08 percent. Those loans are frequently used by homeowners refinancing their mortgages.

To calculate average mortgage rates, Freddie Mac surveys lenders across the country between Monday and Wednesday each week. The average doesn't include extra fees, known as points, which most borrowers must pay to get the lowest rates. One point equals 1 percent of the loan amount.

The average fee for a 30-year mortgage was unchanged from last week at 0.5 point. The fee on 15-year loans also remained at 0.5 point.

Rates on adjustable five-year loans slipped to 3.13 percent from 3.15 percent last week. The fee was unchanged at 0.4 point.