“In April 2015, the city raised its minimum wage from around $9.50 to $11, on the way to $15 an hour by 2017 (for employers with 500 or more employees and certain other employers; the minimum wage for most Seattle businesses rose to $10 in April 2015, and $15 will not go into effect for all Seattle businesses until 2021). The pay of affected workers went up almost 12 percent, compared to a 5 percent increase for workers in nearby, similar places that weren’t bound by the increase. The study’s authors concluded that the increase raised the pay of affected workers by seven percentage points more than might otherwise have occurred.”

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