Mortgage rates inched up again this week, bringing 30-year fixed-rate mortgages back to where they were at the beginning of the month, while demand for purchase loans was down more than 20 percent last week when compared to a year ago.

Rates had been rising steadily this year until mid-March, when economic uncertainty over the crisis in Japan and turmoil in the Middle East had investors seeking safety in bonds, and rates eased.

Investors, at least for now, seem to have put their worries behind them, and money is flowing back into stocks. Reduced demand for bonds that fund most mortgage loans means lower prices and higher yields on those investments — and higher rates for borrowers.

Rates on 30-year fixed-rate mortgage averaged 4.86 percent with an average 0.7 point for the week ending March 31, up from 4.81 percent last week but down from 5.08 percent a year ago, Freddie Mac said in releasing the results of its latest Primary Mortgage Market Survey.

The 30-year fixed-rate mortgage hit an all-time low in Freddie Mac records dating to 1971 of 4.17 percent during the week ending Nov. 11.

For 15-year fixed-rate mortgages, rates averaged 4.09 percent with an average 0.7 point, up from 4.04 percent last week but down from 4.39 percent a year ago. Rates on 15-year fixed-rate mortgages hit a low in records dating back to 1991 of 3.57 percent in November.

Rates on 5-year Treasury-indexed hybrid adjustable-rate mortgage (ARM) loans averaged 3.7 percent with an average 0.7 point, up from 3.62 percent last week but down from 4.1 percent a year ago. The 5-year ARM hit a low in records dating to 2005 of 3.25 percent in November.

For 1-year Treasury-indexed ARMs, rates averaged 3.26 percent with an average 0.6 point, up from 3.21 percent last week but down from 4.05 percent a year ago.

Some analysts fear that as the economic recovery takes hold, rising oil prices and government debt could fuel inflation, which would send mortgage rates up. But inflation as measured by the 12-month growth in the core price index for consumer spending is hovering near the lowest pace since the index was launched in 1960, said Freddie Mac Chief Economist Frank Nothaft.

In a March 15 forecast, economists with the Mortgage Bankers Association said they expect rates on 30-year fixed-rate loans will average 5 percent during the first half of this year, rising to an average of 5.3 percent in the third quarter and 5.5 percent in the final three months of 2011.

The MBA forecast projects rates on 30-year fixed-rate loans will continue a gradual rise next year, climbing to an average of 6.2 percent in the final three months of 2012.

Looking back a week, the MBA said its Weekly Mortgage Applications Survey for the week ending March 25 showed demand for purchase loans was down a seasonally adjusted 1.7 percent from a week earlier, and off 21.9 percent from the same week a year ago.

Requests for refinancings were down 10.1 percent from the previous week, but still accounted for 64.3 percent of all mortgage applications, the group said.