Union membership fell by 400,000 to the lowest level since the 1930s, the Bureau of Labor Statistics announced this past week. As a percentage of the work force, union workers fell from 11.8 percent to 11.3 percent.

One reason for the decline is simply that workers don’t want to join a union when they have the choice. More states have been adopting right-to-work laws, which allow workers to opt out of mandatory unionization, including traditional union stronghold Michigan at the end of last year. Since right to work passed in Indiana last March, unions lost 56,000 members in the state.

Another cause of membership decline is that many former union workers are no longer working. Hostess’s shuttering due to unwavering union demands illustrates the point: when the bakers’ union refused to take a pay cut, the baked goods giant closed its doors and let its 18,000 employees go.

As Heritage President Ed Feulner wrote last fall, “Unions keep losing members as existing unionized firms shrink, and they can’t recruit enough new members to take their place.”

Elliot Gaiser is currently a member of the Young Leaders Program at The Heritage Foundation. For more information on interning at Heritage, please visit http://www.heritage.org/about/departments/ylp.cfm.