Would the United States be better off with only one time zone?

My annual inner monologue suggests two reasons to get up in the morning and go to bed at night: first, to enjoy the sunshine, and second, because that is what everybody else does. But what if the two imperatives collide? What matters more, waking up at the same time as everyone else or waking up with the sun? It might sound like a daft question, but not if you’re a Hong Kong-based journalist filing for a London-based newspaper or a financial analyst in Silicon Valley who needs to be awake when the market opens on Wall Street at 6.30 a.m. Pacific Time.

Rather depressingly, David Letterman outshines the sun in his effect on what people are doing. Push the television schedules an hour later and 5 percent of people will be watching television later—nearly a third of those actually watching the television. But if sunset is an hour later (because the individual is at the western end of a time zone), only half of 1 percent of people will watch later television. The effect also spills over onto sleeping patterns: The television, more than the sunrise, determines when people get up in the morning.