condition mean min max 4 h after light 7.98639 7.62257 8.35021 8 h after light 11.42622 8.77444 14.078 12 h after light 15.082699999999999 14.58 15.5854 4 h after dark 19.7613 17.067 23.1575 8 h after dark 17.528633333333335 16.2097 18.2684 12 h after dark 13.466066666666666 12.2755 14.2738