condition mean min max ZT0-3 66.18183333333333 52.49275 73.76089999999999 ZT4-7 37.080799999999996 37.080799999999996 37.080799999999996 ZT8-11 31.7718 31.7718 31.7718 ZT12-15 34.449325 34.0958 34.80285 ZT16-19 32.497 32.497 32.497 ZT20-23 65.1985 65.1985 65.1985