Union Decline Accounts for Much of Rise in Wage Inequality, Study Finds

The significant decline in union membership since the early 1970s explains approximately 20% of the rising hourly wage inequality among women and about one-third among men, according to a new study in the American Sociological Review.

"Our study underscores the role of unions as an equalizing force in the labor market," co-author Bruce Western, a professor of sociology at Harvard University, told Science Daily. "Most researchers studying wage inequality have focused on the effects of educational stratification - pay differences based on level of education - and have generally under-emphasized the impact of unions."

Looking primarily at full-time, private-sector workers, the study found that the decline in a unionized labor force explains about 33% percent of the rise in wage inequality among men. Among women, de-unionization explains about 20%.

"For generations, unions were the core institution advocating for more equitable wage distribution," said co-author Jake Rosenfeld, a professor of sociology at the University of Washington. "Today, when unions - at least in the private sector - have largely disappeared, that means that this voice for equity has faded dramatically. People now have very different ideas about what's acceptable in terms of pay distribution."