 Shake Shack NYSE:SHAK Inc forecast revenue for its first quarter after-hours on Thursaday which fell short of Wall Street expectations. The burger chain company forecasts revenue for the three months to come in at between US196 million and US201.4 million, compared with an average analyst estimate of US210.9 million, as the coronavirus COVID-19 kept customers away, infected staff and hampered the groups recovery Reportedly, rising paper and food expenses and labor costs also put pressure on margins. 