Ongoing economic concerns continued to push mortgage rates to new lows, as 30-year and 15-year mortgage rates took another dip, pushing home affordability even higher, Freddie Mac reports in its weekly mortgage market survey. 30-year fixed-rate mortgages: averaged 4.15 percent this week, dropping from last week’s 4.32 percent average. The previous record low for 30-year rates was set on Nov. 11, 2010, when rates reached 4.17 percent. For comparison sake, in 2000, 30-year mortgage rates averaged more than 8 percent and just five years ago they averaged 6.5 percent. 15-year fixed-rate mortgages: averaged 3.36 percent, dropping from last week’s 3.50 percent. Last year at this time, the 15-year fixed rate averaged 3.90 percent. 5-year adjustable-rate mortgages: averaged 3.08 percent, dropping from last week’s 3.13 percent. Last year at this time, the 5-year ARM averaged 3.56 percent. 1-year ARM: averaged 2.86 percent this week, dropping from last week’s 2.89 percent. A year ago, the 1-year ARM averaged 3.53 percent. "Not surprising, many home owners took advantage of this low mortgage rate environment and have already refinanced their loans,” says Frank Nothaft, chief economist of Freddie Mac. “The refinance share of applications averaged nearly 70 percent of all mortgage activity in the first half of this year, according to our survey. In addition, an increasing share of refinancing borrowers chose to shorten their loan terms during the second quarter.” Source: “Mortgage Rates Lowest in Over 50 Years,” Freddie Mac (Aug. 18, 2011)