condition mean min max 4 h after light 6.3782000000000005 6.09738 6.5191300000000005 8 h after light 6.093719999999999 6.04113 6.14216 12 h after light 6.14572 6.01513 6.23033 4 h after dark 6.219196666666667 6.1318 6.2889800000000005 8 h after dark 6.2846400000000004 6.1077900000000005 6.54938 12 h after dark 6.38618 6.23493 6.67563