But why do Americans feel so harried? Weirdly, prosperity may be to blame in two ways. First, thanks to rising real incomes, an American's time is worth more now. A walk in the park is more expensive than it used to be. (When people complain to him about being too busy, Mr Hamermesh tells them that their real problem is too much money.) Second, economic advances allow people to squeeze ever more possible activities, both work and leisure, into a day, which encourages people to try to do too much.