U.S. producer prices rose marginally in July as a decline in the cost of energy goods offset higher food prices, pointing to a moderation of inflation pressures at the factory gate. The Labor Department said on Friday its producer price index for final demand edged up 0.1 percent after a 0.4 percent rise in June. Producer inflation data has been volatile since the government revamped the PPI series at the start of the year to include services and construction.