The average 15-year rate dropped to 3.13 percent, a record low. (Victor J. Blue/BLOOMBERG)

The 15-year dropped to 3.13 percent, down from 3.17 one week ago and marking a historic low for the popular refinancing option. One year ago, the average rate stood at 4.15 percent.

Meanwhile, the average 30-year fixed-rate slid back down to 3.88 percent, nearly matching its own all-time low of 3.87 percent set one month ago. That’s down from 3.88 percent last week and well below the 4.88 percent mark set at this time in 2011.

Recently, the trend is helping open the home-buying market to more Americans, according to Frank Nothaft, Freddie Mac vice president and chief economist.

“With these historically low rates and declining house prices, the typical family had more than double the income needed to purchase a median-priced home in January,” Nothaft said in a statement, citing the National Association of Realtors’ latest Housing Affordability Index, which registered the highest reading since records began in 1970.

The Corelogic National National Home Price Index also dropped 3.1 percent year-over-year in January to its lowest level since 2003. Nothaft said that likely explains a recent two-week spike in mortgage applications.

Despite the increase in mortgage applications, tight lending standards and requirements for higher down payments have kept many potential homeowners on the sidelines.

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