Abstract
IN A TYPICAL workweek, one in every four manufacturing production workers in the United States is employed at night. This fraction fluctuates sharply over the business cycle, accounting disproportionately for business cycle changes in employment. The variation in work at night amounts to over 40 percent of the cyclical changes in the employment of manufacturing production workers. While cyclical movements in shiftwork are pervasive in many manufacturing industries, there are also some nonmanufacturing industries in which such variation is important.
