Students at top-ranked schools showed an intriguing pattern: They tend to fall asleep late, after 1 AM, compared to their counterparts further down the rankings, reports Quartz.

The data showed a strong correlation between a school’s 2016 ranking in US News and World Report and student bedtimes. The more elite the college, the later the average bedtime. Columbia students (ranked #4) went to bed latest at 1:26 AM followed by those at University of Pennsylvania (#9), Stanford (#4) and Duke (#8). The earliest bedtimes were for those at the University of Nevada (#187) at 11:54 PM. The military academies were considered a special case given their mandatory schedules.