Estimates of union density by State
http://www.bls.gov/opub/mlr/2001/07/ressum2.pdf

Barry T.Hirsch, David A.Macpherson,
and Wayne G.Vroman
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Union membership as a percentage of
nonagricultural employment,
by State, 1964, 1984, and 2000
Table 1.
                          1964 1984 2000
All States ................... 29.3 19.1 13.6
Alabama ..................... 21.1 15.2 9.8
Alaska ........................ 39.7 24.2 21.9
Arizona ....................... 17.6 9.2 6.6
Arkansas .................... 15.0 10.0 5.9
California .................... 33.0 21.6 16.4
Colorado ..................... 21.2 13.1 9.1
Connecticut ................ 28.8 20.5 16.4
Delaware .................... 29.2 17.9 13.4
District of Columbia ... 18.4 17.5 14.7
Florida ........................ 14.0 9.6 6.9
Georgia ...................... 11.9 10.3 6.3
Hawaii ......................... 21.7 29.2 24.6
Idaho .......................... 24.8 9.5 7.9
Illinois ......................... 35.6 22.6 18.7
Indiana ....................... 40.9 25.4 15.7
Iowa ............................ 27.7 17.4 13.9
Kansas ....................... 21.3 11.9 9.1
Kentucky .................... 25.0 17.3 12.2
Louisiana .................... 18.1 11.1 7.1
Maine .......................... 23.8 19.2 14.3
Maryland .................... 24.7 18.4 14.7
Massachusetts .......... 27.7 21.4 14.4
Michigan ..................... 44.8 29.4 21.0
Minnesota .................. 37.0 23.1 18.4
Mississippi ................. 15.4 9.7 6.1
Missouri ................. 27.1 20.0 13.3
Montana ................. 37.4 18.6 14.3
Nebraska ............... 23.0 14.0 8.6
Nevada .................. 33.3 23.9 17.3
New Hampshire ...... 24.3 10.4 10.5
New Jersey ............ 39.4 25.0 20.9
New Mexico ........... 14.1 9.8 8.3
New York ................ 35.5 32.3 25.7
North Carolina ....... 8.4 7.5 3.7
North Dakota ......... 17.3 12.7 6.6
Ohio ....................... 37.6 23.9 17.5
Oklahoma .............. 15.8 10.4 6.9
Oregon ................... 38.9 25.1 16.5
Pennsylvania ......... 37.7 25.0 17.0
Rhode Island ......... 26.0 22.5 18.3
South Carolina ....... 7.0 4.2 4.1
South Dakota ......... 14.1 11.0 5.7
Tennessee ............. 22.1 13.5 8.9
Texas ..................... 13.5 8.0 5.9
Utah ....................... 23.8 13.4 7.5
Vermont ................. 18.5 11.5 10.4
Virginia ................... 15.8 10.8 5.7
Washington ............ 44.5 26.3 18.5
West Virginia ......... 36.5 24.1 14.4
Wisconsin .............. 34.0 25.0 17.9
Wyoming ................ 21.0 15.7 8.5
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NOTE: Figures represent the percentage of each
State's nonagricultural wage and salary employees
who are union members. Estimates for the 1964-2000
period are based on a combination of the 1983-2000
Current Population Survey Outgoing Rotation Group
(CPS-ORG) earnings files, the 1973-81 May CPS
earnings files, and the BLS publication, Directory
of National Unions and Employee Associations for
various years. Figures for all years, 1964 to
present, are available from the authors.
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