condition mean min max 4 h after light 9.5 9.5 9.5 8 h after light 13.75 5.2 22.3 12 h after light 12.65 3.5 21.8 4 h after dark 3.65 2.3 5.0 8 h after dark 15.2 10.4 20.0 12 h after dark 20.0 10.7 29.3