WASHINGTON » Long-term U.S. mortgage rates edged higher this week for a second straight week. They still are near historically low levels to encourage potential homebuyers.

Mortgage giant Freddie Mac said today the average for the benchmark 30-year fixed-rate mortgage rose to 3.48 percent from 3.45 percent last week. The average rate is down sharply from 3.98 percent a year ago.

The 15-year fixed mortgage rate increased to 2.78 percent from 2.75 percent last week.

The low rates, along with a solid job market, have been bolstering the housing market as it recovers from the bust that began nine years ago. Americans bought new homes in June at the fastest pace in more than eight years, the Commerce Department reported Tuesday.

New-home sales rose 3.5 percent last month to a seasonally adjusted rate of 592,000, the best level since February 2008. Purchases of new homes have climbed 10.1 percent year-to-date, despite volatile sales on a monthly basis.

Still, the U.S. homeownership rate fell in the second quarter to match the lowest level on record in 1965, the year the U.S. Census Bureau started publishing the figures, according to Census data issued today. The homeownership rate in the April-June period was 62.9 percent, down 0.5 percentage point from 63.4 percent in the second quarter of 2015.

Affordability remains a problem and the potential for new-home sales to regain their historic average sales rate of 650,000 could be limited.

To calculate average mortgage rates, Freddie Mac surveys lenders across the country at the beginning of 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 remained at 0.5 point this week. The fee for a 15-year loan also was unchanged from last week at 0.5 point.

Rates on adjustable five-year mortgages averaged 2.78 percent, unchanged from last week. The fee was steady at 0.5 point.