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Labor productivity, defined as output per hour, fell 6.4 percent in the overall mining sector between 2006 and 2007.
This drop was led by a large productivity decline of 15.4 percent in metal ore mining (NAICS 2122), where hours rose rapidly.
Unit labor costs rose in all of the mining industries in 2007. Unit labor costs represent the cost of labor required to produce one unit of output.
This information is from the BLS Productivity and Costs Program. Additional information is available from "Productivity and Costs by Industry: Selected Service-Providing and Mining Industries, 2007" (PDF) (HTML), news release USDL 09-0546.
Bureau of Labor Statistics, U.S. Department of Labor, The Economics Daily, Decline in mining productivity at https://www.bls.gov/opub/ted/2009/may/wk3/art04.htm (visited June 03, 2023).