condition mean min max ZT0-3 0.9207175000000001 0.478528 1.3763200000000002 ZT4-7 0.6433180000000001 0.6433180000000001 0.6433180000000001 ZT8-11 0.6047735 0.6047735 0.6047735 ZT12-15 1.3559425 1.07983 1.632055 ZT16-19 1.6685400000000001 1.6685400000000001 1.6685400000000001 ZT20-23 1.7564899999999999 1.7564899999999999 1.7564899999999999