Effective February 5, 2004, Productivity and Cost measures for the manufacturing sector
are now reported using the 2002 North American Industry Classification System (NAICS).
Because of the reclassification, these measures are not directly comparable with
manufacturing measures published on or before Dec. 3, 2003.
For further information, please visit the Bureau Of Labor Statistics web
site at http://www.bls.gov/lpc/home.htm
Source: US. Bureau of Labor Statistics
Release: Productivity and Costs
US. Bureau of Labor Statistics, Manufacturing Sector: Real Output Per Hour of All Persons [OPHMFG], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/OPHMFG/, June 29, 2015.