Recovery in the manufacturing sector in the U.S. is showing signs of slowing down.

The Institute for Supply Management (ISM) announced on Monday that its manufacturing index stood at 51-point-three last month, down from 54-point-two in February. The index is an economic measure of the U.S. business sector.

A reading above 50 indicates expansion in manufacturing and a reading below 50 means contraction.

An index measuring new orders of manufacturers slipped from 57-point-eight to 51-point-four between February and March.