On the heels of poor housing data, mortgage rates declined across the board after spiking last week, according to data released Thursday by Freddie Mac.

The 30-year average slipped back below the 4.0 percent threshold this week. (Amy Sancetta/AP)

The hybrid adjustable-rate mortgages each fell 0.06 percent last week, with the 5-year ARM average declining from 2.96 percent to 2.90 percent and the 1-year ARM average slipping from 2.84 percent to 2.78 percent.

Frank Nothaft, vice president and chief economist for Freddie Mac, pinned the declining rates to a series of weak housing economic indicators released in the past week.

“The S&P/Case Shiller 20-City Composite home price index slid in January to its lowest reading since December 2002,” Nothaft said in a statement. “In addition, new home sales declined 0.5 percent in February, below the market consensus of an increase, and pending existing home sales also declined for the month.”

On the other hand, new data released Thursday by the National Association of Realtors shows that sales of investment and vacation homes surged 64.5 percent to 1.23 million last year, lifting the combined market share to its highest level since 2005.

Earlier this week, The Federal Housing Finance Agency’s inspector general called for more scrutiny of Fannie Mae and Freddie Mac, which own or guarantee about half of all mortgages in the United States and have received huge infusions of taxpayer cash. The inspector general said the regulator is currently failing to adequately evaluate the two companies’ actions.

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