A quarter of U.S. employees do some work between 10 p.m. and 6 a.m.

That’s a lot, compared with about seven percent in France and the Netherlands. The U.K. is closest to the U.S. on this measure, where 19 percent work during night hours. On the weekends, one in three workers in the U.S. were on the job, compared to one in five in France, Germany, and the Netherlands.

All of this adds up: According to the OECD, the U.S. leads the way in average annual work hours at 1,790—200 more hours than France, the Netherlands, and Denmark. That works out to about 35 hours a week, but a recent Gallup poll found the average to be much higher than that—at 47 hours weekly. And perhaps that’s not surprising, when 55 percent of college grads report that they get their sense of identity from their work.