condition mean min max 4 h after light 19.362897 16.234095 22.491699 8 h after light 17.43641 14.71271 20.16011 12 h after light 16.2332895 15.506903 16.959676 4 h after dark 15.6721045 15.614628 15.729581 8 h after dark 16.5414515 16.123227 16.959676 12 h after dark 18.995914 18.995914 18.995914