WASHINGTON (AP) — Long-term U.S. mortgage rates crept higher this week, upping the costs of borrowing to purchase a home just as more of the millennial generation is entering the real estate market.

Mortgage buyer Freddie Mac said Thursday that the average rate on 30-year fixed-rate mortgages rose to 4.40 percent this week, a slight gain from 4.38 percent last week. That average is the highest since April 2014 and the seventh straight weekly increase.

The rate on 15-year, fixed-rate loans rose to 3.85 percent from 3.84 percent last week.

Mortgage rates closely track the yield on 10-year U.S. Treasury notes, which have climbed to 2.92 percent from 2.46 percent at the start of the year. Interest costs are rising in response to greater government debt levels and expectations of higher inflation.