condition mean min max 4 h after light 3.1 3.1 3.1 8 h after light 9.75 3.0 16.5 12 h after light 1.75 1.6 1.9 4 h after dark 2.75 2.6 2.9 8 h after dark 3.45 2.1 4.8 12 h after dark 1.9000000000000001 1.6 2.2