AVERAGE CUSTOMARY FULL-TIME HOURS PER WEEK, AVERAGE EARNINGS PER HOUR, AND AVERAGE FULL-TIME WEEKLY EARNINGS, AND INDEX NUMBERS THEREFOR, IN SPECIFIED YEARS, BY OCCUPATION-Continued

AVERAGE CUSTOMARY FULL-TIME HOURS PER WEEK, AVERAGE EARNINGS PER HOUR, AND AVERAGE FULL-TIME WEEKLY EARNINGS, AND INDEX NUMBERS THEREFOR, IN SPECIFIED YEARS, BY OCCUPATION-Continued

AVERAGE CUSTOMARY FULL-TIME HOURS PER WEEK, AVERAGE EARNINGS PER HOUR, AND AVERAGE FULL-TIME WEEKLY EARNINGS, AND INDEX NUMBERS THEREFOR, IN SPECIFIED YEARS, BY OCCUPATION-Continued

AVERAGE CUSTOMARY FULL-TIME HOURS PER WEEK, AVERAGE EARNINGS PER HOUR, AND AVERAGE FULL-TIME WEEKLY EARNINGS, AND INDEX NUMBERS THEREFOR, IN SPECIFIED YEARS, BY OCCUPATION-Concluded

Effect of Changes in Hours of Work on Output

HE effect of changes in the hours of work on output is the sub

Tject of an article by Otto Lipmann in the International

Labor Review, April, 1924 (pp. 481-506). The writer takes up the question of the 8-hour day entirely from the economic standpoint and analyzes the existing data on the relation between hours of work and production, showing the extreme complexity of the problem and the danger of attributing changes in output entirely to changes in the working hours.

Because of the period of lowered production following the war and also to meet the demand of the workers for a reduction in hours, the 8-hour day became fairly general in many of the European countries. The principal reasons advanced by the workers for the introduction of the shorter workday were the need for greater leisure for rest and recreation, and the excessive fatigue following too great prolongation of the hours of work. The present tendency, however, with the necessity for increased production, is to disregard these claims, except as excessive fatigue has the effect of diminishing output, on the ground that they must yield to the demands of the economic situation. The writer does not discuss the extent to which such opinion is justified, but states:

Even if all social and ethical considerations or those prompted by interest in the worker are ignored, the question is to find, not the maximum of which the worker is capable, but the optimum, i. e., the amount of work which produces the largest output with the least possible use of machinery, power, etc. It is obviously uneconomical to run machinery at full capacity when labor is working only at half or quarter capacity.

Although it has been recognized for many years that some limitation of the hours of work is necessary, as yet the optimum, or the "normal working-day," has not been determined, and still less the right length of the day for different kinds of work. Reduction of hours of work of individual workers may be accomplished either by shortening the hours of work of the establishment or by increasing the number of shifts. For example, for one shift of 10 hours may be substituted a working-day of 16 hours with two 8-hour shifts, the 24-hour day instead of being divided into 2 shifts of 12 hours may be divided into 3 shifts of 8 hours each, or the hours of work of the undertaking may be reduced, as from 10 to 8 hours, at the same time as those of the individual workers.

The effect of shortened working hours may be estimated either by the difference in output in a calendar period (day, week, or year) or in hourly output as compared with that before the change in hours. If hourly output increases, the reduction in hours may be profitable even though the output in a calendar period decreases, since many of the costs of production such as power, depreciation, heating, lighting, and wages depend on hours of work and not on the calendar period. In order that there shall be no actual reduction in output, hourly output must increase in the same proportion that hours are reduced. It can not be assumed, however, that a change in hourly output occurring in connection with a change in the working hours is an effect of the latter change, since there are many other factors which enter into the situation. For this reason an increase in hourly output can not be ascribed solely to the reduction in hours