Days of Work over a Half Century: The Rise of the Four-Day Workweek.

This article analyzes the rising prevalence of four-day workweeks among full-time workers in the United States from 1973 to 2018, using data from the Current Population Survey (CPS) and the American Time Use Survey (ATUS). The incidence of four-day workweeks tripled during this period, adding approximately 7 million workers, with similar trends observed in the Netherlands, Germany, and South Korea. The increase is not explained by demographic shifts, industrial changes, establishment size, commuting times, or irregular shifts, but is associated with worker preferences and daily fixed costs of working, such as childcare and commuting. An equilibrium model and metropolitan-level analysis suggest that supply-side factors (worker preferences) rather than demand-side factors (employer characteristics) primarily drive the growth, accompanied by a declining wage penalty for four-day schedules. The findings highlight the importance of considering days worked per week as a distinct dimension of labor supply and suggest further research into the underlying causes and implications of this shift.