Following the Black Friday strikes and protests at more than 1,600 Wal-Mart Stores Inc. (NYSE: WMT) locations across the United States, fast-food workers will walk off the job in 160 cities on Thursday as a movement called the Fight for $15 spreads. Workers at McDonald’s Corp. (NYSE: MCD), Wendy’s Co. (NASDAQ: WEN), Burger King Worldwide Inc. (NYSE: BKW), Yum! Brands Inc.’s (NYSE: YUM) KFC, and Domino’s Pizza Inc. (NYSE: DPZ) are expected to take part.

According to a Monday media advisory from BerlinRosen, since the first strike in 2012 in New York City, 7.6 million low-wage workers across the country have gotten raises through local ballot measures, city and state legislation and contract negotiations. Organizers are expecting first-time strikes this year in Jackson, Miss.; Knoxville, Tenn.; and Buffalo, N.Y.

The fast-food industry has been a target of demands for higher pay for the past two years. According to a recent study by public policy research group Demos, an average full-time worker at McDonald’s earns $9.09 an hour, or about $18,900 a year:

[F]ast food paychecks are unlikely to reflect even [that much] income, because workers are unlikely to get paid for 40 hours on the clock per week. The average work week in the industry amounts to just 24 hours and schedules can change from week to week erratically, making paychecks unpredictable and vitiating any attempts of involuntary part-time workers to find supplementary jobs. An employee in a fast food restaurant earning the average wage for the average hours brings home less than $12,000 per year.

The cities of Seattle and San Francisco have raised the minimum wage to $15 an hour. Four additional states — Alaska, Arkansas, Nebraska and South Dakota — approved ballot measures in the recent elections to increase minimum wages with no specific target. Right now, 23 states and the District of Columbia have set a minimum wage above the federal minimum of $7.25 an hour.

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