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In 2006, the union membership rate for government workers (36.2 percent) was nearly five times that of private industry workers (7.4 percent).
Within the public sector, local government workers had the highest union membership rate, 41.9 percent. This group includes several heavily unionized occupations, such as teachers, police officers, and fire fighters.
Among major private industries, transportation and utilities had the highest union membership rate, at 23.2 percent, followed by construction (13.0 percent). The information industry and manufacturing also had double-digit unionization rates in 2006.
These 2006 data on union membership are from the Current Population Survey. Unionization data are for wage and salary workers. Find out more in "Union Members in 2006" (PDF) (TXT), news release USDL 07-0113.
Bureau of Labor Statistics, U.S. Department of Labor, The Economics Daily, Union membership by industry, 2006 at https://www.bls.gov/opub/ted/2007/feb/wk1/art05.htm (visited April 01, 2023).