condition mean min max 4 h after light 8.0430925 7.737677 8.348508 8 h after light 7.564401 7.48266 7.646142 12 h after light 8.263242 7.681735 8.844749 4 h after dark 8.227398 7.681735 8.773061 8 h after dark 7.485567 6.953715 8.017419 12 h after dark 7.986423 7.986423 7.986423