Economic activity in the U.S. manufacturing sector contracted in May, according to the purchasing managers index for manufacturing released today by the Institute for Supply Management. The index reading of 49.0 was at its lowest level since June 2009 — and only readings above 50.0 indicate the manufacturing economy is generally expanding.

Bloomberg reported it was the fastest contraction in four years and economist had forecast growth.

The employment portion of the index edged down to a reading of 50.1 in May from 50.2 in April, showing decelerating growth.