condition mean min max 4 h after light 520.4 520.4 520.4 8 h after light 668.05 636.5 699.6 12 h after light 1282.05 1132.5 1431.6 4 h after dark 1697.65 1468.8 1926.5 8 h after dark 1332.1 1220.5 1443.7 12 h after dark 1175.0 568.9 1781.1