condition mean min max 4 h after light 1998.4 1998.4 1998.4 8 h after light 2359.7 2319.9 2399.5 12 h after light 2433.7 2401.2 2466.2 4 h after dark 2767.6 2485.0 3050.2 8 h after dark 2974.05 2812.2 3135.9 12 h after dark 2709.7 2372.1 3047.3