condition mean min max ZT0-3 5.0978916666666665 3.386145 5.980684999999999 ZT4-7 1.95715 1.95715 1.95715 ZT8-11 3.0562899999999997 3.0562899999999997 3.0562899999999997 ZT12-15 2.8646649999999996 2.83539 2.8939399999999997 ZT16-19 3.87018 3.87018 3.87018 ZT20-23 7.237665 7.237665 7.237665