condition mean min max 4 h after light 8.5495525 8.175347 8.923758 8 h after light 8.088258 8.001169 8.175347 12 h after light 7.6760895 7.666155 7.686024 4 h after dark 8.175347 8.175347 8.175347 8 h after dark 8.2667585 7.921574 8.611943 12 h after dark 8.158927 8.158927 8.158927