condition mean min max ZT0-3 17.534346666666668 7.086790000000001 22.9486 ZT4-7 3.8327299999999997 3.8327299999999997 3.8327299999999997 ZT8-11 11.40635 11.40635 11.40635 ZT12-15 19.8251 16.72955 22.920650000000002 ZT16-19 21.54495 21.54495 21.54495 ZT20-23 26.7446 26.7446 26.7446