WASHINGTON (AP) -- Average U.S. rates on fixed mortgages rose this week for a second straight week but remained near historic lows.

Mortgage buyer Freddie Mac said Thursday the average rate for a 30-year loan increased to 4.20 percent from 4.14 percent last week. The average for the 15-year mortgage jumped to 3.31 percent from 3.23 percent.

Rising prices and higher interest rates beginning in mid-2013 have made homes less affordable for would-be buyers. At the same time, a limited supply of homes is available to buy. Mortgage rates are about a quarter of a percentage point higher than they were at the same time last year.

Mortgage rates tend to follow the yield on the 10-year Treasury note. The 10-year note traded at 2.64 percent Wednesday, up from 2.60 percent a week earlier and 2.44 percent the previous week. Speculation over the European Central Bank’s decision last week to cut interest rates to the point of charging banks for depositing money at the ECB sent foreign buyers into the U.S. bond market.