WASHINGTON - U.S. manufacturing expanded for the 14th straight month in July in a good sign for the overall economy.

The Institute for Supply Management, a trade group of purchasing managers, reported Friday that its manufacturing index rose to 57.1, highest level since April 2011 and up from 55.3 in June.

Anything above 50 signals that manufacturing is growing.

Paul Dales, senior U.S. economist at Capital Economics, wrote in a research note that the index was consistent with overall economic growth of 3.5 percent.

The U.S. economy already has been showing renewed strength. Economic growth clocked in an impressive 4 percent annual pace from April through June after getting off to a bad start the first three months of the year. And the Labor Department said Friday that employers added more than 200,000 jobs in July for the sixth straight month. Factories created 28,000 jobs in July, most since November. In the past year, manufacturers have added 178,000, best 12-month stretch of hiring since November 2012.

Dales wrote that the ISM report "suggests that manufacturing payrolls may soon start to rise by close to 50,000 a month rather than July's 28,000."

American factories have been busy. The Commerce Department reported last week that orders for durable goods rose 0.7 percent in June, and a category seen as a proxy for business investment plans rose a healthy 1.4 percent.

The ISM reported that new orders, production and employment at factories rose. Exports declined last month. Seventeen of 18 industries covered by the survey showed growth last month. Only wood products contracted.