US producer prices were flat in August as the cost of energy products declined and trade services fell, but underlying producer inflation firmed, Reuters reported. The US Department of Labor said today the unchanged reading in its producer price index for final demand followed a 0.4% drop in July. In the 12 months through August, the PPI was unchanged after decreasing 0.2% in July Producer prices have been dampened by a strong dollar and cheaper oil. But some of the drag is easing with the dollar rally appearing to have peaked early this year and oil prices having pushed off multi-decade lows.