Average mortgage rates for 30-year, fixed-rate loans rose off record lows in the week ending Thursday, the Federal Home Loan Mortgage Corp. said. Average rates for 30-year contracts climbed from 3.67 percent to 3.71 percent with 0.7 points. Thirty-year mortgage rates averaged 4.5 percent the same week of 2011. Average rates on 15-year contracts also rose after establishing a low in the previous week. Average rates on 15-year loans rose from 2.94 percent to 2.98 percent with 0.7 points. A year earlier, rates on 15-year contracts stood at 3.67 percent. Five-year adjustable rate mortgages averaged 2.8 percent in the week with an average 0.6 points, down from an average of 2.84 percent in the previous week. Five-year adjustable rate loans averaged 3.27 percent a year earlier. Average rates on one-year treasury-indexed adjustable mortgages defied the trend and fell during the week. Interest rates dropped from 2.79 percent to 2.78 percent with an average 0.5 points. A year ago, rates for these loans averaged 2.97 percent.