WASHINGTON, June 4 (Xinhua) -- Business activity in the U.S. service sector grew in May for the second straight month but at a slower pace than in April, the Institute for Supply Management reported Monday.

    The Arizona-based research group Tempe said its index of business activity in the non-manufacturing sector registered 51.7, down from 52.0 in the previous month.

    A reading above 50 indicates expansion, while one below indicates contraction. The index fell in January to 44.6, its first drop below 50 since March 2003, and remained below 50 in February and March. Analysts were expecting a reading of 50.3 for May.

    The new orders index for May climbed to 53.6 from 50.1 percent in March while the index for new export orders rose to 54.0 from 48.5.

    The employment index, however, declined to 48.7 from 50.8. The prices index jumped to 77.0 from 72.1, indicating a faster rate of price increase compared to April.

    Thirteen industries reported growth last month, including real estate, mining, utilities, construction and information, while seven industries reported contraction, which included transportation, finance and insurance, forestry, agriculture, fishing and hunting.

    The service sector -- including everything from restaurants and hotels to banks and airlines -- represents about 80 percent of economic activity in the United States.