WASHINGTON – Private-sector payrolls increased 91,000 in August, led by the service-producing sector and small businesses, according to the ADP employment report released Wednesday.

Economists were predicting the ADP figure would rise by about 100,000.

The expansion for July was revised down to 109,000 from a prior estimate of 114,000.

The report “suggests that the trend in employment moderated somewhat in August at a pace below what would be consistent with a stable unemployment rate,” said Joel Prakken, chairman of Macroeconomic Advisers, which produces the report from anonymous payrolls data supplied by Automatic Data Processing Inc.

According to ADP, service-sector employment rose 80,000 in August, compared with 11,000 for the goods-producing sector. Small-business employment rose 58,000, compared with 30,000 for medium businesses and 3,000 for large businesses.

Markets look to ADP’s report on private-sector payrolls to provide some guidance on the U.S. government’s jobs estimate, which will be released Friday and includes information on both private- and public-sector payrolls.

Analysts polled by MarketWatch expect Friday’s Bureau of Labor Statistics employment report to show meager overall growth of 53,000, compared with 117,000 in July, and unemployment to remain at 9.1 percent.

The ADP report did not capture a Verizon strike of 45,000 workers — a strike that will cut the Bureau of Labor Statistics’ report, said Ted Wieseman of Morgan Stanley.

“The BLS survey is based on people actually working and getting paid during the pay period including the week of the 12th of each month. ADP, on the other hand, does not measure whether a person was paid or working during the BLS reference period, only whether that person was listed on an ADP payroll record. So the ADP report misses temporary job disruptions from strikes and bad weather,” Wieseman wrote in a research note.