U.S. construction spending unexpectedly fell in September amid declines in outlays on both private and public projects.

The Commerce Department said on Monday that construction spending dropped 0.5% after edging up 0.1% in August. Economists polled by Reuters had forecast construction spending gaining 0.4%.

Construction spending increased 7.8% on a year-on-year basis in September. The government reported last week that gross domestic product increased at a 2.0% annualized rate, stepping down from the April-June’s robust 6.7% pace.

Spending on private construction projects decreased 0.5% in September after falling 0.3% in August. Outlays on residential construction dropped 0.4% after nudging up 0.1% in August. Single-family homebuilding spending declined 0.6% and outlays on multi-family housing projects slipped 0.3%.

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