condition mean min max ZT0-3 22.926012 22.926012 22.926012 ZT4-7 20.257035000000002 20.257035000000002 20.257035000000002 ZT8-11 18.949917 18.949917 18.949917 ZT12-15 22.642175 22.642175 22.642175 ZT16-19 20.121160500000002 20.121160500000002 20.121160500000002 ZT20-23 18.7725765 18.7725765 18.7725765