NEW YORK (CNN/Money) - Long-term mortgage rates nudged higher for the sixth straight week, Freddie Mac said Thursday, boosted by inflation fears.

The average rate on 30-year fixed-rate mortgages climbed to 6.01 percent, with an average 0.7 of a point payable up front, up from 5.95 percent the previous week. Last year at this time, the rate on the 30-year fixed-rate loan stood at 5.40 percent.

The average 15-year mortgage rate averaged 5.56 percent, with a 0.7 percent payable up front, up from 5.47 percent the previous week. A year ago, the 15-year rate averaged 4.70 percent.

"Renewed concern over the threat of inflation pushed up long-term mortgage rates, while the most recent Fed statement caused short-term rates to float upwards," said Frank Nothaft, Freddie Mac vice president and chief economist. "Although mortgage rates have risen these past six weeks, they still remain at very affordable levels.

"Although mortgage rates are beginning to rise, we have yet to experience much of a slow down in the housing market," Nothaft said.

Five-year adjustable-rate mortgages (ARMs) averaged 5.35 percent, with an average 0.7 point payable up front, up from 5.31 percent the week before. There is no data available for a year-to-year comparisons since Freddie Mac began tracking this mortgage rate at the start of 2005.

One-year adjustable rate mortgages (ARMs) averaged 4.24 percent, up from last week's 4.20 percent, with an average 0.8 of a point payable up front. At this time last year, the one-year ARM rate averaged 3.36 percent.

Freddie Mac's (down $0.37 to $63.31, Research) average mortgage rates are based on a survey of 125 lenders nationwide.

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