condition mean min max 4 h after light 1.9 1.9 1.9 8 h after light 5.65 1.0 10.3 12 h after light 9.25 0.8 17.7 4 h after dark 5.55 0.7 10.4 8 h after dark 4.6000000000000005 0.8 8.4 12 h after dark 5.25 0.5 10.0