The nation's manufacturing sector contracted in November for the first time in more than three years, a trade group said Friday.

The Institute for Supply Management, based in Tempe, Ariz., said its manufacturing index registered 49.5 in November, behind October's reading of 51.2. The last time the sector contracted was in April 2003. A reading below 50 indicates contraction, while a number above 50 points to expansion.

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The sector had been growing for 41 consecutive months.

November's index came in below the average analyst expectation for a reading of 52.

The index was one of two worrisome economic reports Friday. The Commerce Department said construction activity in October plummeted by the largest amount since 2001, and home building fell for the seventh month in a row.

The ISM report said that employment in the manufacturing sector shrank in November, with a 49.2 reading compared with 50.8 in October.

The new orders index fell to 48.7 in November, compared with 52.1 in October. The production index also contracted, dropping to 48.5 from 51.9 last month.

The prices paid index rose to 53.5, after falling to 47 in October.

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