WASHINGTON - Average U.S. rates on fixed mortgages dropped this week to their lowest levels in four months, a positive sign for the housing recovery.

Mortgage buyer Freddie Mac says the average rate on the 30-year loan fell to 4.13 percent. That's down from 4.28 percent. The average on the 15-year fixed loan declined to 3.24 percent from 3.33 percent.

Both averages are the lowest since June 20.

Mortgage rates have been falling since September, when the Federal Reserve held off slowing its $85-billion-a-month in bond purchases. The bond buys are intended to keep longer-term interest rates low, including mortgage rates.

And a slowdown in hiring in September makes it more likely that the Fed will continue its stimulus into next year.

Mortgage rates tend to follow the yield on the 10-year Treasury note. The 10-year note traded at 2.50 percent Wednesday, down sharply from 2.61 percent last Thursday.

To calculate average mortgage rates, Freddie Mac surveys lenders across the country on Monday through Wednesday 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 ticked up to 0.8 point from 0.7 point. The fee for a 15-year loan declined to 0.6 point from 0.7 point.

The average rate on a one-year adjustable-rate mortgage fell to 2.60 percent from 2.63 percent. The fee rose to 0.5 point from 0.4 point.

The average rate on a five-year adjustable mortgage dropped to 3.00 percent from 3.07 percent. The fee was unchanged at 0.4 point.