Mortgage rates decreased a bit from last week, reflecting the fact that weaker housing data is putting downward pressure on average fixed mortgage rates.

The 30-year fixed-rate mortgage (FRM) averaged 4.23 percent for the week ending Feb. 6, down from last week when it averaged 4.32 percent. A year ago at this time, the 30-year FRM averaged 3.53 percent.

The 15-year FRM this week averaged 3.33 percent, down from last week when it averaged 3.4 percent. A year ago at this time, the 15-year FRM averaged 2.77 percent.

The five-year Treasury-indexed hybrid adjustable-rate (ARM) averaged 3.08 percent this week, down from last week when it averaged 3.12 percent. A year ago, the five-year ARM averaged 2.63 percent.

The one-year Treasury-indexed ARM averaged 2.51 percent this week, down from last week when it averaged 2.55 percent. At this time last year, the one-year ARM averaged 2.53 percent.

"Mortgage rates fell further this week following the release of weaker housing data. The pending home sales index fell 8.7 percent in December to its lowest level since October 2011," Frank Nothaft, vice president and chief economist at Freddie Mac, said in a statement. "Fixed residential investment negatively contributed to GDP in the fourth quarter for the first time since the third quarter of 2010. Also, the Institute for Supply reported a significant slowing in growth in the manufacturing industry in December than the market consensus forecast."