Economic activity in the U.S. service sector increased in April but at the same rate as in March, according to the Institute for Supply Managements' nonmanufacturing index released today.

The index's April reading of 55.4 was unchanged from March's reading. However, readings of more than 50 indicate expansion.

The employment portion of the index lost ground in April, falling to a reading of 49.5 from 49.8 in March.