Mortgage rates jumped sharply this week, with the average rate on the benchmark conforming 30-year fixed mortgage rate rising to 4.89 percent, according to Bankrate.com's weekly national survey. The average 30-year fixed mortgage has an average of 0.36 discount and origination points.

The average 15-year fixed mortgage zoomed upward to 4.26 percent, and the larger jumbo 30-year fixed rate did as well, settling at 5.39 percent. Adjustable rate mortgages were mostly higher, with the average 5-year ARM climbing to 3.85 percent and the average 7-year ARM increasing to 4.22 percent.

Mortgage rates have been on a consistent upswing, rising in four of the five weeks since the Federal Reserve's early November announcement of $600 billion in additional bond purchases to stimulate the economy. But the movement kicked into overdrive this week with the tax cut extension expected to generate hundreds of billions more in government borrowing. Bond investors haven't responded kindly to the prospects of additional supply, with bond prices falling and bond yields rising. Mortgage rates are closely related to yields on long-term government bonds.

The last time mortgage rates were above 6 percent was Nov. 2008. At that time, the average rate was 6.33 percent, meaning a $200,000 loan would have carried a monthly payment of $1,241.86. With the average rate now 4.89 percent, the monthly payment for the same size loan would be $1,060.24, a savings of $181 per month for a homeowner refinancing now.

SURVEY RESULTS

30-year fixed: 4.89% - up from 4.71% last week (avg. points: 0.36)

15-year fixed: 4.26% - up from 4.07% last week (avg. points: 0.36)

5/1 ARM: 3.85% - up from 3.74% last week (avg. points: 0.4)