WASHINGTON – New construction of U.S. housing units rebounded in January to the fastest pace in four months, the Commerce Department reported Wednesday.

A big increase in multifamily units offset a decline in starts of single-family homes to drive an increase of 14.6 percent to a seasonally adjusted annual rate of 596,000.

The gain in January showed a rebound from December’s revised pace of 520,000 units, the lowest since April 2009.

The monthly report is volatile, and the longer-term trend shows a weak housing market. In the past four months, housing starts have averaged 549,000 annualized, down only slightly from 550,000 in the four months ending in December.

In a healthy economy, builders start about 1 million units a year.

Starts of single-family homes fell 1.0 percent to a 413,000 rate, while starts of multifamily units jumped 80 percent to 171,000.

Housing usually leads economic recoveries, but this year the sector has lagged behind for several seemingly intractable factors.

The biggest is that the labor market remains weak. There is also an enormous amount of supply on the market, including many foreclosed homes.