WASHINGTON — Rates on 30-year mortgages fell for the third straight week, dropping to the lowest level in five months.

Freddie Mac, the mortgage company, reported yesterday that 30-year fixed-rate mortgages dipped to 6.24 percent this week, down from 6.26 percent last week.

It was the third straight weekly decline after rates hit 6.40 percent. Analysts attributed the decreases to mounting evidence that the economy is starting to slow.

"Reports of weaker consumer spending in September and a decline in manufacturing activity in October kept mortgages at bay this week," said Frank Nothaft, chief economist at Freddie Mac.

The Federal Reserve last week cut a key interest rate by a quarter-point, marking the second rate reduction in the past six weeks. Fed officials, however, disappointed investors by signaling that there may not be further rate cuts, given their worries about higher inflation from surging energy prices and a weaker dollar.

Mortgage rates fell across the board this week.

Rates on 15-year fixed-rate mortgages averaged 5.90 percent, down from 5.91 percent.