I find the study by the University of Michigan (cited at 1:09) interesting that Japanese workers slept less than 7:30 hours on average. That doesn't seem to be

I find the study by the University of Michigan (cited at 1:09) interesting that Japanese workers slept less than 7:30 hours on average. That doesn't seem to be an outrageously low number. As a matter of fact, in the first year or so after my son was born, I regularly slept much less than that, and not just for some weeks. I personally like sleeping, but I know at least two people who don't and try to minimize the amount of sleep they take. I'm sure one of them does quite a bit less than 7:30 a night on average.