- A groundbreaking new paper, “Unions and Inequality Over the Twentieth Century: New Evidence from Survey Data,” overturns economic orthodoxy and shows that unions reduce inequality. Published by the National Bureau of Economic Research, it shows that the growth of union membership—which reached its height of nearly 30 percent in 1955, before falling to its current low of 10.7 percent—had a significant, equalizing effect on the income distribution during the midcentury’s “Great Compression.”