condition mean min max ZT0-3 34.54985 34.54985 34.54985 ZT4-7 30.6033 30.6033 30.6033 ZT8-11 17.12055 17.12055 17.12055 ZT12-15 28.55095 28.55095 28.55095 ZT16-19 29.143549999999998 29.143549999999998 29.143549999999998 ZT20-23 34.7125 34.7125 34.7125