30-Year Mortgage Rates Lowest in 6 Months: Thirty-year fixed-rate mortgages averaged 7.86% this week, the lowest in more than six months, according to a national survey released by the Federal Home Loan Mortgage Corp. It was the lowest since April 4, when rates averaged 7.78%. Rates had been as high as 8.34% as recently as the week ended Sept. 5. They averaged 8.06% last week. On one-year adjustable-rate mortgages, lenders were asking an average initial rate of 5.68%, down from 5.7% last week. Fifteen-year mortgages averaged 7.38% this week, down from 7.58% a week earlier. The rates do not include points.