that time they are essentially operating like shift workers if we add those two groups together would we say it's what uh a third of Americans I would say half of America half of America yeah if you take teenagers because you know high school students and college students because again going back to horacio's uh study because Horatio also collected activity data from high school students and college students and we have replicated that with high school students and college students in San Diego so that's Seattle and San Diego and this study now there are many sleep researchers that have been collecting this data and what we find is um typically the high school students they are going to beds around midnight and college students at least the UCSD students we found maybe one out of 100 who went to bed before midnight