According to the U.S. Department of Labor, the national union membership rate was 11.1 percent in 2015 (the same as in 2014). Washington's total union membership rate was 16.8 percent in 2015, also unchanged since 2014.
Professors Barry Hirsch of Georgia State University and David Macpherson of Trinity University have updated their database, which shows the public and private union membership numbers for each state.
In 2015, Washington's public-sector union membership rate was 46.1 percent and its private-sector union membership rate was 11.0 percent. (In 2014, the public-sector union membership rate was 48.5 percent and the private-sector rate was 10.9 percent.)
In terms of absolute numbers, union membership in Washington rebounded slightly after declines in 2014, for both private- and public-sector workers. But public-sector employment increased more than public-sector union membership (7.5 percent vs. 2.1 percent), leading to a decline in the rate.
For both public and private workers, Washington's union membership rates remain higher than they are nationally.