Another problem for unions is an aging membership that is not being replaced by younger members. By age, the union membership rate was highest among workers age 55 to 64 (14.9 percent) and lowest among those 16 to 24 (4.2 percent).
In New York, the state with the highest union density, nearly one-quarter of the workforce belonged to a union. North Carolina had the lowest at 2.9 percent.
Among full-time wage and salary workers, union members in 2012 had median weekly earnings of $943, while those who were not union members earned $742.
Bureau of Labor Statistics: http://www.bls.gov
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