condition mean min max 4 h after light 4.1 4.1 4.1 8 h after light 8.4 2.5 14.3 12 h after light 9.299999999999999 2.9 15.7 4 h after dark 1.85 1.8 1.9 8 h after dark 1.9 1.3 2.5 12 h after dark 13.5 8.7 18.3