In 1930 the British economist John Maynard Keynes predicted that the biggest problem facing future generations would be what to do with all their leisure time.

Well, here we are in Keynes’s future: Where is that leisure we were promised?

Though the average hours at work have certainly decreased in the last century, it doesn’t necessarily follow that leisure has increased, since nonlabor time is not necessarily leisure. Any attempt to compare changes in leisure over long periods of time has to confront some tricky issues of definition.

The most recent attempt to examine long-term trends in leisure is by two economists, Valerie A. Ramey of the University of California, San Diego, and Neville Francis of the University of North Carolina. Next time you get a chance, you can download the paper from http://www.econ.ucsd.edu/~vramey/research/Historical_Hours.pdf.But if you never find the time, it’s no wonder. According to Ms. Ramey and Mr. Francis, the amount of leisure time per capita hasn’t changed much in the last 105 years.

Since this view is at odds with a number of other studies, it is worth going over their analysis to see how they reach this somewhat surprising conclusion.