WASHINGTON (AP) — Average U.S. rates on fixed mortgages fell this week for the second straight week as the spring home-buying season begins.

Mortgage buyer Freddie Mac says the average rate for the 30-year loan fell to 4.27 percent from 4.34 percent last week. The average for the 15-year mortgage eased to 3.33 percent from 3.38 percent.

Mortgage rates have risen about a full percentage point since hitting record lows about a year ago.

Many analysts have been expecting an improving economy to lift the housing market, which has been recovering over the past two years. But housing has struggled to maintain momentum. Rising home prices and higher mortgage rates have held back some potential home buyers. Others have had trouble qualifying for mortgages.