For a century, two labour market empirical regularities characterized the movements of the hours of work, employment and hourly compensation of American manufacturing production workers. They resembled conditional labour supply functions. Increases in employment substituted for reductions in hours per worker. The implied elasticities of hours and employment with respect to hourly earnings declined in absolute value over time. The activities of trade unions and the effects of statutory legislation contribute to the explanations for what is observed. Recently, changes in real hourly earnings contribute little to understanding movements in hours of work and in employment of these workers.

中文翻译：

---

19 世纪到 21 世纪美国制造业工人的工时、就业和收入

一个世纪以来，两个劳动力市场经验规律表征了美国制造业生产工人的工作时间、就业和每小时薪酬的变动。它们类似于有条件的劳动力供给函数。就业的增加取代了每个工人工作时间的减少。随着时间的推移，小时和就业相对于小时收入的隐含弹性在绝对值上下降。工会的活动和法定立法的影响有助于解释所观察到的情况。最近，实际每小时收入的变化对了解这些工人的工作时间和就业变化几乎没有帮助。