condition mean min max ZT0-3 31.481899999999996 29.2165 33.747299999999996 ZT4-7 15.879850000000001 15.879850000000001 15.879850000000001 ZT8-11 17.145400000000002 17.145400000000002 17.145400000000002 ZT12-15 0 0 0 ZT16-19 47.832049999999995 47.832049999999995 47.832049999999995 ZT20-23 49.267399999999995 49.267399999999995 49.267399999999995