What is "Time in bed"?

“Time in bed” is found in the sleep graph in the Events page.

"Time in bed" is the difference between “Time out of bed” and “Time to bed" giving you a view of how long an individual spends in bed on a given night.
For example, if the individual goes to bed at 11 p.m. and leaves the bed at 7 a.m., “Time in bed” will be 8 hours.