NEW YORK (CNN/Money) - Mortgage rates slipped this week, according to a report released Thursday.

The rate on 30-year fixed-rate mortgages averaged 5.75 percent in the week ended Sept. 16, with an average 0.8 point payable up front, down from last week when it averaged 5.83 percent, Freddie Mac said.

A year earlier, the rate on the 30-year fixed-rate loan averaged 6.16 percent.

"The consumer price index figures released this morning showed that the run up in oil prices has not been inflationary at the consumer level, much to the relief of mortgage lenders," said Frank Nothaft, Freddie Mac vice president and chief economist. "And price stability in products other than oil have allowed for more money to go toward home buying and home projects."

The 15-year mortgage rate dropped to a 5.13 percent average this week from 5.22 percent last week, with 0.8 point payable up front. Last year, the average rate stood at 5.46 percent.

One-year adjustable rate mortgages (ARMs) averaged 4.03 percent, up from 4.0 percent last week, with 0.7 of a point payable up front. At this time last year, the average rate for ARMs was 3.87 percent.

"Next week the policy committee of the Federal Reserve will meet and our expectation is that it will raise short-term rates by a quarter of a percent. However, we also don't see this increase as having a significant impact on long-term mortgage rates," said Nothaft.

Freddie Mac's (FRE: up $0.20 to $67.74, Research, Estimates) average mortgage rates are based on a survey of 125 lenders nationwide.