condition mean min max ZT0-3 185.17371666666668 55.32115 421.265 ZT4-7 200.1095 200.1095 200.1095 ZT8-11 92.71164999999999 92.71164999999999 92.71164999999999 ZT12-15 247.09199999999998 144.434 349.75 ZT16-19 92.35249999999999 92.35249999999999 92.35249999999999 ZT20-23 44.96795 44.96795 44.96795