The pace of U.S. job losses continued to slow in September as the private sector shed fewer jobs than in the previous month, according to a report offering a preview of government data due Friday.

Meanwhile, gross domestic product decreased at a 0.7% annual rate in the second quarter, better than the 1% decline previously estimated, the Commerce Department said Wednesday. It was a big improvement over GDP's 6.4% decline in the first quarter.

Private...