WASHINGTON – Construction of new U.S. homes sank in October to the lowest level in 18 months, but the number of building permits issued rose slightly, the Commerce Department reported Wednesday.

Housing starts dropped 11.7 percent to an annualized rate of 519,000 last month, with nearly all of the decline occurring in the volatile multi-dwelling segment. Construction of condominium and apartment buildings with five or more units sank 47.5 percent.

The last time starts were that low was in April 2009.

Yet new construction on single-family homes, which account for 75 percent of the housing market, barely fell, according to the latest government data. Single-family starts dipped 1.1 percent from September and are little changed over the past four months.

What’s more, building permits increased 0.5 percent in October to an annualized rate of 547,000, with single-family permits rising for the first time in seven months. Permits for September were also revised slightly higher.

Economists view permits as a more accurate barometer of future demand.