Dalton Conley, a sociologist at NYU, has an op-ed in today’s New York Times arguing that something novel has happened to the life of leisure: it isn’t very leisurely anymore. “[I]t is now the rich who are the most stressed out and the most likely to be working the most. Perhaps for the first time since we’ve kept track of such things, higher-income folks work more hours than lower-wage earners do.”

Conley hypothesizes that this intriguing development is the result of greater disparity in incomes at the top end of the scale — what he calls an “economic red shift.” That is, the richer you are, the faster people at the wealth level just above you seem to be pulling away. Combine that with the fact that people usually define their socioeconomic status in relative terms — i.e., how they compare to the Joneses — and you have an explanation for why hours increase with income. Or, as Conley puts it, at higher income levels, “the opportunity cost of not working is all the greater ( … since the higher we go, the more relatively deprived we feel).”