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Union membership has plummeted in the U.S., from nearly one-third of workers 50 years ago to one in 10 American workers today. Quoctrung Bui of NPR’s Planet Money created this fascinating map to illustrate how union membership has changed across America since 1964. (This is just an animated gif: You can see the full interactive version here.)

The map shows an especially sharp drop in union membership in the Midwest, which in the 1960s had a high concentration of manufacturing jobs. In the last few decades, both the share of manufacturing jobs and the proportion of manufacturing jobs held by union workers fell. The map also shows that unions have never really been popular in the South, largely due to political opposition.

The most unionized state in the U.S. today is New York, which has an exceptionally high rate of unionization among government workers: 71 percent of New York government workers are unionized, compared to 36 percent nationwide on average. Alaska and Hawaii have the second and third highest rates of union membership, in part because government jobs make up a bigger share of their job markets than in other parts of the country.

Unions remain deeply contentious in America. Neoclassical economics considers a union a monopoly on the supply of labor, and thus a kind of market inefficiency. Yet other economic studies suggest that the decline of unions has lead to changing realities for workers that are not so pretty – including stagnating wages for men, and even a decline in marriage.

Map republished courtesy of Quoctrung Bui and Planet Money.

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