condition mean min max ZT0-3 1.3007076666666666 0.6713180000000001 1.71174 ZT4-7 0.270934 0.270934 0.270934 ZT8-11 0.5625910000000001 0.5625910000000001 0.5625910000000001 ZT12-15 0.387837 0.2811295 0.49454450000000005 ZT16-19 1.325512 1.325512 1.325512 ZT20-23 1.7003249999999999 1.7003249999999999 1.7003249999999999