condition mean min max 4 h after light 8.923439 8.723665 9.123213 8 h after light 8.493608 8.263551 8.723665 12 h after light 9.4764995 8.723665 10.229334 4 h after dark 8.9243165 8.175347 9.673286 8 h after dark 8.770941 7.728776 9.813106 12 h after dark 9.258026 9.258026 9.258026