Fitbit tracked users’ sleep stages and ended up with 6 billion nights of sleep for data, which is the biggest set of sleep data ever assembled, according to Inc.

The biggest takeaway among all of their data was that you should consistently go to sleep around the same time.

Going to sleep around the same time on a consistent basis is important to avoid social jet lag. An example could be someone who goes to sleep at 11 p.m. on weeknights and wakes up at 7 a.m. But on the weekends, they stay out and don’t fall asleep until 2:30 a.m. and wake up around 10 a.m.

This affects not only your body but also your performance at work, because you’re getting less sleep due to your normal rhythm and routine times of falling asleep being off.