A new survey by Japan's health ministry shows that Japan's younger people are overworked and more exhausted than their elders. Here are the highlights in three charts:

1. Young adults are unhappier than older people. Japanese between the ages of 20 and 39 rated their happiness at 6.03 out of 10, compared with 6.25 for those between the ages of 40 and 64, and 6.92 for people over 65.

Among...