condition mean min max ZT0-3 26.93838333333333 22.03095 34.787099999999995 ZT4-7 34.014300000000006 34.014300000000006 34.014300000000006 ZT8-11 55.1537 55.1537 55.1537 ZT12-15 51.756524999999996 46.3253 57.187749999999994 ZT16-19 28.9991 28.9991 28.9991 ZT20-23 19.16875 19.16875 19.16875