Facebook Inc. FB, +0.25% said Monday it will raise the minimum wage by 33% to $20 per hour for contract workers but only in the San Francisco's Bay Area, New York City and Washington, D.C., given the relatively higher costs of living in those cities. For Seattle, the social media company said the minimum wage is rising 20% to $18 per hour. For content reviewers, the minimum wage is being raised even more, to $22 an hour for those in the Bay Area, NYC and D.C., to $20 an hour for those in Seattle, and to $18 an hour in all other U.S. metro areas. Facebook had raised its minimum wage to $15 an hour in 2015. "In the years since, it's become clear that $15 per hour doesn't meet the cost of living in some places where we operate," said Janelle Gale, vice president of human resources, and Arun Chandra, vice president of scaled operations. Facebook said it will implement the wage changes by the middle of 2020, and that it is working to develop similar standards for other countries. Facebook's stock fell 3.2% in afternoon trade. It has run up 39.1% year to date, while the S&P 500 SPX, +0.30% has gained 12.2% and the Nasdaq Composite COMP, +0.42% has climbed 15.5%.