condition	mean	min	max
4 h after light	4.123305	4.04879	4.19782
8 h after light	13.2259	13.0097	13.4421
12 h after light	19.8009	18.5715	21.0303
4 h after dark	19.0704	16.5095	21.6313
8 h after dark	8.908215	8.25727	9.55916
12 h after dark	5.980145	5.61157	6.34872