condition mean min max 4 h after light 0.7 0.7 0.7 8 h after light 7.5 0.9 14.1 12 h after light 7.6 4.1 11.1 4 h after dark 4.55 3.4 5.7 8 h after dark 10.15 1.2 19.1 12 h after dark 2.5 1.6 3.4