The union membership rate, the percent of wage and salary workers who were members of unions, was 11.1 percent in 2015, unchanged from 2014, according to the US Bureau of Labor Statistics.
Workers in protective service occupations and in education,
training, and library occupations had the highest unionization
rates at 36.3 percent and 35.5 percent, respectively.
Private sector union membership rate, 24.2% in 1973, 6.6%: in
2014. Public sector rose sharply in the 1970s and has been
relatively steady since 1980 at around 35 percent, more than
five times higher than that of private-sector workers.
Overall union membership has fallen by about a half since 1983,
according to the Bureau of Labor Statistics.