Industrial production rose 0.6 percent in September after posting a gain of 0.4 percent in August, the U.S. Federal Reserve said Monday. Manufacturing output in August rose marginally, up 0.1 percent. Production at mines rose 0.2 percent, posting a sixth consecutive monthly increase. Output at utility companies rose 0.4 percent, climbing after five months of declines, the central bank said. Total production in August was equal to its 2007 average and 3.2 percent above the level of September 2012, the Fed said. The rate of capacity utilization among industrial firms -- the percentage of production compared to companies going at full steam -- edged up 0.4 percentage points higher to 78.3 percent in August. That rate is 1.9 percentage points below its historic average, using data from 1972 through 2012.