By Ben Leubsdorf

WASHINGTON -- The U.S. budget deficit widened last month compared with a year earlier, and forecasters anticipate a growing mismatch between government spending and revenues in the coming years.

The federal government ran a $27.52 billion deficit in December, the Treasury Department said Thursday, nearly double the monthly deficit of $14.44 billion in December 2015.

Economists surveyed by The Wall Street Journal had expected a $22.6 billion deficit last month.

Total receipts in December were down 9% from the same month a year earlier, according to Treasury data, and federal outlays fell 5% on the year.

Calendar quirks related to the New Year's Day holiday meant some federal paymentsfor January were counted in December. Also, the Federal Reserve in late 2015 had made a one-time $19.3 billion payment to the Treasury under the terms of a federal highway bill that tapped the central bank's surplus capital account as a source of funding.

In the 12 months ended December, the federal budget deficit totaled $580.14 billion, up about 21% from the $477.97 billion deficit in the 12 months ended December 2015. As a share of U.S. economic output, the deficit was roughly 3.1% of gross domestic product in the 2016 calendar year, up from about 2.6% in the 2015 calendar year.

The federal government's fiscal year begins in October.

Following years of declining deficits in the wake of the 2007-09 recession, the budget gap has started to widen. The nonpartisan Congressional Budget Office last year estimated the deficit would total 3.1% of GDP in the current fiscal year.

The CBO projected the deficit would rise over thenext decade as spending growth outpaces revenues, reaching 4.6% of GDP in the 2026 fiscal year -- assuming no major changes to current law and continued modest economic growth. Big changes could be coming, however, as President-elect Donald Trump and the Republican-controlled Congress have made overhauling the tax code a top priority.

Write to Ben Leubsdorf at ben.leubsdorf@wsj.com

(END) Dow Jones Newswires

January 12, 2017 14:15 ET (19:15 GMT)

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