TEMPE, AZ—The Institute for Supply Management said its manufacturing index rose to 55.3 percent last month from 54.2 percent in February. The latest reading exceeded the MarketWatch forecast of 54.6 percent.

TEMPE, AZ—U.S. manufacturing unexpectedly jumped to the highest since May 2004 as orders, production and employment all picked up, according to the Institute for Supply Management's August report.

WASHINGTON-—U.S. factory activity rose to the highest level in 13 years last month as hurricanes disrupted supplies but drove up demand for manufactured goods. The Institute for Supply Management said its September manufacturing index rose to 60.8 from 58.8 in August, the highest reading since May 2004.