WASHINGTON (12/20/10)--The average rate on both 30-year and 15-year fixed-rate mortgages continued to rise last week, posting double digit basis point increases. As reported in Freddie Mac's mortgage rate survey for the week ended Dec. 16, both mortgage rates continued to rise for the fifth week, with 30-year mortgages averaging 4.83% and 15-year mortgages averaging 4.17%. Those mortgage rates averaged 4.61% and 3.96% during the week ended Dec. 9, respectively. Both five-year and one-year adjustable rate mortgages remained low, with average rates of 3.77% and 3.35% reported. Freddie Mac Vice President/Chief Economist Frank Nothaft noted that the mortgage rate averages were the highest reported since March. For the full release, use the resource link.