As union membership declines, income inequality increases: Union membership and share of income going to the top 10%, 1917–2021
| Union membership rate | Share of income going to the top 10% | |
|---|---|---|
| 1917 | 11.00% | 45.0% |
| 1918 | 12.10% | 44.0% |
| 1919 | 14.30% | 45.9% |
| 1920 | 17.50% | 44.1% |
| 1921 | 17.60% | 47.4% |
| 1922 | 14.00% | 46.1% |
| 1923 | 11.70% | 43.7% |
| 1924 | 11.30% | 45.7% |
| 1925 | 11.00% | 47.2% |
| 1926 | 10.70% | 47.6% |
| 1927 | 10.60% | 47.1% |
| 1928 | 10.40% | 48.2% |
| 1929 | 10.10% | 47.0% |
| 1930 | 10.70% | 46.3% |
| 1931 | 11.20% | 46.3% |
| 1932 | 11.30% | 48.3% |
| 1933 | 9.50% | 48.0% |
| 1934 | 9.80% | 49.1% |
| 1935 | 10.80% | 48.1% |
| 1936 | 11.10% | 48.4% |
| 1937 | 18.60% | 47.5% |
| 1938 | 23.90% | 47.1% |
| 1939 | 24.80% | 48.6% |
| 1940 | 23.50% | 48.9% |
| 1941 | 25.40% | 47.0% |
| 1942 | 24.20% | 42.3% |
| 1943 | 30.10% | 38.9% |
| 1944 | 32.50% | 36.1% |
| 1945 | 33.40% | 35.3% |
| 1946 | 31.90% | 37.0% |
| 1947 | 31.10% | 36.9% |
| 1948 | 30.50% | 38.9% |
| 1949 | 29.60% | 38.3% |
| 1950 | 30.00% | 39.1% |
| 1951 | 32.40% | 37.9% |
| 1952 | 31.50% | 36.6% |
| 1953 | 33.20% | 35.7% |
| 1954 | 32.70% | 36.0% |
| 1955 | 32.90% | 36.7% |
| 1956 | 33.20% | 35.7% |
| 1957 | 32.00% | 35.7% |
| 1958 | 31.10% | 35.5% |
| 1959 | 31.60% | 36.0% |
| 1960 | 30.70% | 35.5% |
| 1961 | 28.70% | 35.6% |
| 1962 | 29.10% | 36.2% |
| 1963 | 28.50% | 36.6% |
| 1964 | 28.50% | 37.0% |
| 1965 | 28.60% | 36.7% |
| 1966 | 28.70% | 36.3% |
| 1967 | 28.60% | 35.3% |
| 1968 | 28.70% | 35.5% |
| 1969 | 28.30% | 34.1% |
| 1970 | 27.90% | 33.5% |
| 1971 | 27.40% | 34.1% |
| 1972 | 27.50% | 34.4% |
| 1973 | 27.10% | 34.6% |
| 1974 | 26.50% | 33.6% |
| 1975 | 25.70% | 34.0% |
| 1976 | 25.70% | 33.9% |
| 1977 | 25.20% | 34.3% |
| 1978 | 24.70% | 34.0% |
| 1979 | 25.40% | 34.3% |
| 1980 | 23.60% | 33.9% |
| 1981 | 22.30% | 34.3% |
| 1982 | 21.60% | 34.6% |
| 1983 | 20.1% | 35.3% |
| 1984 | 18.8% | 36.5% |
| 1985 | 18.0% | 36.6% |
| 1986 | 17.5% | 36.3% |
| 1987 | 17.0% | 37.5% |
| 1988 | 16.8% | 39.3% |
| 1989 | 16.4% | 38.8% |
| 1990 | 16.0% | 38.8% |
| 1991 | 16.0% | 38.3% |
| 1992 | 15.7% | 39.4% |
| 1993 | 15.7% | 39.1% |
| 1994 | 15.5% | 39.2% |
| 1995 | 14.9% | 39.9% |
| 1996 | 14.5% | 40.8% |
| 1997 | 14.1% | 41.5% |
| 1998 | 13.9% | 41.9% |
| 1999 | 13.9% | 42.3% |
| 2000 | 13.4% | 42.8% |
| 2001 | 13.3% | 42.0% |
| 2002 | 13.3% | 41.5% |
| 2003 | 12.9% | 41.6% |
| 2004 | 12.5% | 42.4% |
| 2005 | 12.5% | 43.6% |
| 2006 | 12.0% | 44.3% |
| 2007 | 12.1% | 44.0% |
| 2008 | 12.4% | 43.6% |
| 2009 | 12.3% | 42.5% |
| 2010 | 11.9% | 43.9% |
| 2011 | 11.8% | 44.3% |
| 2012 | 11.3% | 45.6% |
| 2013 | 11.3% | 44.9% |
| 2014 | 11.1% | 45.6% |
| 2015 | 11.1% | 45.5% |
| 2016 | 10.7% | 45.3% |
| 2017 | 10.7% | 45.5% |
| 2018 | 10.5% | 45.8% |
| 2019 | 10.3% | 45.7% |
| 2020 | 10.8% | 44.4% |
| 2021 | 10.3% | 45.6% |
Source: Data on union membership follow the composite series found in Historical Statistics of the United States through 1982, updated through 2021 using Bureau of Labor Statistics, series ID: LUU0204899600. Income inequality (share of income to top 10%) data are from the World Income Database.