Productivity in Manufacturing and the Length of the Working Day

Data from the manuscript census of manufacturing are used to estimate the effects of the length of the working day on output and wages. We find that the elasticity of output with respect to daily hours worked was positive but less than one—implying diminishing returns to increases in working hours. When the annual number of days worked is held constant, the average annual wage is found to be positively related to daily hours worked, but again the elasticity less than 1.0. At the modal value of daily hours (10 hours per day), it appears that from the standpoint of employers, the marginal benefits of a shorter working day (a lower wage bill) were approximately offset by the marginal cost (lower output).