Work schedules that fall anywhere outside the hours of 7 am to 6 pm are considered shift work. These schedules may consist of fixed hours, rotating or split shifts, or irregular work times. According to the Bureau of Labor Statistics, roughly 16% of full-time salary and wage workers in the U.S. worked non-daytime shifts in 2017 and 2018. Recently, many employees have also been forced to take on shift work in recent months due to the COVID-19 pandemic.