[pluijzer]

I didn't put any effort in my source. I just googled for 'average sleep time Americans' an quoted the featured result. It wasn't really meant as a statement just a silly segue in to telling about the benefits of sleep. Both sources didn't really make it clear whether this is the time sleeping + trying to fall asleep, or actual sleep. I myself unfortunately take a full hour to fall asleep and wake up at 4 for at least another half an hour. Anyway, it is good to include nap-times because these do count towards your total amount of sleep. It doesn't have to be continues.