NEW YORK (CNN/Money) - The U.S. service sector, which makes up the bulk of the world's biggest economy, was strong in February despite a slight slowdown in growth, the nation's purchasing managers said Wednesday.

The Institute for Supply Management's index of non-manufacturing activity came in at 53.9, compared with 54.5 in January. Economists, on average, expected a reading of 53, according to Briefing.com.

It was the 13th straight month the index was above 50.0, a level that indicates expansion in the sector.

The report, compiled from a survey of about 370 businesses in banking, real estate, entertainment and other service industries, had little impact on U.S. stock prices, which were slightly higher in early trading. Treasury bond prices also rose.

The non-manufacturing sector is critical to the broader economy, providing more than 80 percent of all U.S. jobs. Consumer spending on services alone makes up 39 percent of the entire economy.

But the ISM report indicated that service-sector employers are set to reduce their hiring -- the employment component of the broader index dropped to 49 from 50.3 in January.

The new orders index fell to 53 from 56.2, while the price index rose to 60.9 from 57 -- a clear sign that the lack of pricing power that's hurting manufacturers does not extend to service providers.