… is, on this “Equal Pay Day,” from page 57 of Thomas Sowell’s 2008 book, Economic Facts and Fallacies:
The replacement of human muscle by machine power, and the growing importance of industries and occupations not dependent on either, have made sex differences and age differences no longer as significant as they had once been. The economic consequences could be seen in the rising age at which people reached their peak earnings, now that experience and skill were more important than physical strength. Other economic consequences included reductions in male-female pay differentials, even before laws were passed mandating equal pay for equal work.