condition mean min max 4 h after light 1.6 1.6 1.6 8 h after light 3.5 1.5 5.5 12 h after light 5.3 1.9 8.7 4 h after dark 5.85 3.3 8.4 8 h after dark 14.7 11.6 17.8 12 h after dark 24.0 3.5 44.5