Mortgage rates held at record low levels this week, with the average conforming 30-year fixed mortgage rate at 4.88 percent, according to Bankrate.com's weekly national survey. The average 30-year fixed mortgage has an average of 0.48 discount and origination points.

The average 15-year fixed mortgage inched lower to another record low of 4.32 percent while the larger jumbo 30-year fixed rate declined to 5.70 percent. Adjustable rate mortgages were mixed, with the average 1-year ARM remaining at 4.87 percent while the average 5-year ARM notched higher to 4.19 percent.

Mortgage rates remain at record lows as a byproduct of ongoing uncertainty about the economy and nervousness among investors. A "flight to quality" among global investors has driven Treasury yields significantly lower, and mortgage rates are closely tied to yields on long-term government debt. As long as there is lingering doubt about the sustainability of the U.S. economic recovery, mortgage rates will remain at near present levels.

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 4.88 percent, the monthly payment for the same size loan would be $1,059.02, a savings of $182 per month for a homeowner refinancing now.

SURVEY RESULTS

30-year fixed: 4.88% - unchanged from last week (avg. points: 0.48)

15-year fixed: 4.32% - down from 4.33% last week (avg. points: 0.49)

5/1 ARM: 4.19% - up from 4.16% last week (avg. points: 0.40)