Mortgage rates fell to new lows for the week ending Feb. 2 as economic data showed weaker than expected economic growth, Freddie Mac said Thursday. 

The McLean, Va.-based government-sponsored enterprise released its primary mortgage market survey, which shows the average 30-year, fixed-rate mortgage falling from 3.98% last week to 3.87%. The 30-year FRM hit 4.81% a year ago.

Meanwhile, the 15-year FRM fell to 3.14% from 3.24% the previous week and 4.08% last year. The 5-year Treasury-indexed hybrid adjustable-rate mortgage also declined from 2.85% to 2.8%. 

The only rate that rose is the 1-year Treasury-indexed ARM, which hit 2.76%, up from 2.74% last week, but down from 3.26% last year. 

"Most mortgage rates eased to all-time record lows this week as fourth-quarter growth in the economy fell short of market projections," said Frank Nothaft, vice president and chief economist of Freddie Mac.

"The gross domestic product rose 2.8% in the final three months of 2011, below the market consensus forecast of 3%, while consumer spending in December was flat. One bright spot, however, was that fixed residential investment increased for the third consecutive quarter and residential construction spending rebounded in December, rising 0.7%."

Bankrate also reported falling mortgage rates, with the 30-year FRM dropping from 4.25% last week to 4.12%, and the 15-year FRM declining from 3.45% to 3.34%. The 5-year adjustable rate mortgage also declined from 3.09% to 3.02%.