NEW YORK (CNN/Money) - A closely watched measure of manufacturing activity in the Chicago area surged in May, the region's purchasing managers said Friday, stronger than most economists expected.

The National Association of Purchasing Management-Chicago said its index of regional manufacturing jumped to 52.2 from 47.6 in April. Any reading above 50 signals expansion in the sector. Economists, on average, expected the Chicago PMI index to rise to just 48.8, according to a Reuters poll.

The index had slipped below 50 in March, showing contraction for the first time in five months. The pullback sparked concern about the U.S. economic recovery.

The employment component of the index fell to 43.6 from 43.7 in April. Prices paid fell to 53.7 from 55.9 last month.  

--from staff and wire reports