U.S. Service Sector Growth Unexpectedly Slows

A measure of U.S. nonmanufacturing economic activity showed the service industries expanded at a slower pace in May, but continued to grow -- a sign of resilience in the large service sector that powers the U.S. economy.

The Institute for Supply Management on Friday said its index of nonmanufacturing activity fell to 52.9 in May, down 2.8 percentage points from 55.7 in April. Economists surveyed by The Wall Street Journal expected a smaller tick down to 55.5.

A reading above 50 indicates that services activity is expanding, while a reading below 50 signals contraction. May marked the 76th month of expansion in the service sector of the economy, which covers everything from banking to burger chains.

Write to Anna Louie Sussman at anna.sussman@wsj.com