The pace of business activity in the U.S. Midwest in August rebounded more than expected from the month before, signaling a pickup in that region's economy, a report showed on Friday.

The Institute for Supply Management-Chicago business barometer shot up to a three-month high of 64.3 in August from 52.6 in July. Economists were looking for a July reading of 56.0.

It was the index's biggest monthly point gain since July 1983 and marked a sharp recovery from July's reading, which had marked a 13-month low.

(Reporting by Dan Burns; Editing by Meredith Mazzilli)