Alan Diaz, File, Associated Press
In this July 24, 2015 file photo, Esteban Lopez Perez rolls a cigar at a local cigar store in the Little Havana area in Miami.

WASHINGTON — U.S. factories were a little less busy last month.

The Institute for Supply Management's manufacturing index slipped to 52.7 last month from 53.5 in June. Economists had expected the index to remain unchanged. Any reading above 50 indicates growth.

The index was inadvertently released before the scheduled publication time of 10 a.m. Eastern Daylight Time, the institute said. The cause of the early release "is being researched by our team," said Bradley Holcomb, chair of ISM's manufacturing business survey committee.

The index had risen in May and June before slipping last month. It hit a 12-month high of 58.1 last August.

Factories' exports are contracting, partly because a strong dollar makes U.S. goods more expensive.

"There are a lot of things that are weighing on exports," Holcomb said, citing the strong dollar, China's economic slowdown and uncertainty about a resolution to the Greek debt crisis.

Hiring slowed at U.S. factories last month, but production and new orders rose.

"The manufacturing sector will probably continue to struggle as the dollar has appreciated further recently and overseas demand has remained muted," Adam Collins, an economist at Capital Economics, wrote in a research report. "However, activity in other, larger parts of the economy has remained strong."

The Commerce Department reported last Monday that orders to U.S. factories for big-ticket goods rose sharply in June, though the gain was driven by a surge in demand for commercial aircraft — a volatile category.

The U.S. economy is plugging along. It grew at a 2.3 percent annual pace from April through June, rebounding from a bitter winter. Unemployment fell in June to 5.3 percent, lowest in seven years.


This story has been corrected to show that the Institute for Supply Management, not the Institute of Purchasing Managers, compiled the manufacturing index.