I go to sleep around 10:30 on work nights, and it takes until about 11-11:30 to drift off. I then wake up/fall back asleep approximately every 30 minutes to an hour until around 1:30.

After than I usually sleep really soundly until around 4:30 or 5. Then it's back to waking up/falling back asleep every 30 minutes to an hour until I get up for work at 6:30.

I don't know how that rates? Is that 5? Average?