condition mean min max 4 h after light 6.9220985 6.746547 7.09765 8 h after light 6.931523 6.29962 7.563426 12 h after light 7.4273785 7.222101 7.632656 4 h after dark 7.342569 6.721119 7.964019 8 h after dark 7.1311505 6.820933 7.441368 12 h after dark 6.762018 6.762018 6.762018