Mortgage rates fell for the second week straight, hitting a six week low and assisting in homebuyer affordability during the spring home buying season.

According to the latest Freddie Mac Primary Mortgage Market Survey, the average 30-year, fixed-rate mortgage averaged 4.27% for the week ending April 17, down from 4.34% a week ago, but up from 3.41% a year earlier.

Furthermore, the 15-year FRM decreased to 3.33%, a fall from last week’s 3.38%, but significantly up from 2.64% for the same period in 2013.

The 5-year Treasury-indexed hybrid adjustable-rate mortgage averaged 3.03% this week, down from 3.09% a week ago, but up from 2.60% last year.

The 1-year Treasury-indexed reached 2.44% this week, slightly up from 2.41% a week prior and 2.63% in 2013.

“Mortgage rates continued to ease this week as housing starts rose 2.8% in March but not as much as expected," Frank Nothaft, vice president and chief economist with Freddie Mac, said. "Also, permits fell 2.4% in March to a seasonally adjusted annual rate of 990,000, which followed a slight downward revision of 4,000 permits in February."

Similarly, Bankrate reported mortgage rates falling further, with the 30-year, FRM dropping to 4.43% from 4.47% last week.

The 15-year, FRM decreased to 3.48%, down from 3.52% last week, while the 5/1 ARM declined to 3.32% from 3.34% a week prior.

“Mortgage rates dropped for the second week in a row amid mixed economic news abroad and in the United States," said Polyana da Costa, senior mortgage analyst at Bankrate.com.  "Despite some recent economic news, the United States is still perceived by investors as one of the safest places to park their money.  Whenever investors seek safety in U.S. Treasuries and mortgage bonds, the yields on those investments tend to fall.  Mortgage rates normally follow that trend."