CHICAGO, IL - JANUARY 28: In this photo illustration a cheeseburger is served up at a Shake Shack restaurant on January 28, 2015 in Chicago, Illinois. The burger chain, with currently has 63 locations, is expected to go public this week with an IPO priced between $17 to $19 a share. The company will trade on the New York Stock Exchange under the ticker symbol SHAK. (Photo Illustration by Scott Olson/Getty Images)