WASHINGTON (AP) - Average long-term U.S. mortgage rates barely moved this week, remaining close to historically low levels as the spring home-buying season gets underway.

WASHINGTON (AP) Average long-term U.S. mortgage rates barely moved this week, remaining close to historically low levels as the spring home-buying season gets underway.

Mortgage giant Freddie Mac says the national average for a 30-year fixed-rate mortgage ticked up to 3.70 percent from 3.69 percent last week.

The average rate for a 15-year mortgage, popular with homeowners who refinance, edged up to 2.98 percent from 2.97 percent last week.

A year ago, the average 30-year mortgage rate was 4.41 percent and the 15-year mortgage rate was 3.47 percent. Mortgage rates have remained low even though the Federal Reserve in October ended its monthly bond purchases, designed to hold down long-term rates.

More Americans signed contracts to buy homes in February, the National Association of Realtors reported Monday.