THE LENGTH OF THE WORK DAY: Explanations 4

Demand and Supply

The highest hours occupations and industries in the 1890s were no longer necessarily the highest hours occupations and industries in recent times. For example, in the 1890s professionals, crafts workers, and laborers worked a much shorter day compared to managers, service, and sales workers. By industry the longest hours worked were in trade and personal service and the shortest in mining and construction. In 1991 managers and sales workers still worked the longest day but service and clerical the shortest. By industry the longest hours were in mining, transportation, communications, utilities, and trade and the shortest in entertainment and personal service. If some of the occupations or industries that experienced large hours declines (perhaps because these were the industries that experienced the greatest degree of technical change) were the occupations or industries that employed many low decile workers, then hours of workers in the lowest deciles may have fallen simply because they were over-represented in the occupations or industries that experienced declines in hours. This point can be quantified as follows. Suppose that the daily hours of a worker in wage decile i, hi, can be written as
w6504-7

w6504-8
where Hj is the average number of daily hours worked in occupation or industry j, a tJ is the ratio of daily hours worked in wage decile i to average occupation or industry hours and the fraction of workers in wage decile i in occupation or industry j. Then, the horizontal shift in demand for daily hours of work from an individual in wage decile i due to changes in the interoccupational or interindustrial mix of daily hours at fixed wages is

w6504-9
where ог, and аг] are evaluated at the base year.