condition mean min max ZT0-3 9.56648796825 8.557086286499999 10.57588965 ZT4-7 3.53987969275 3.3505975865 3.729161799 ZT8-11 3.634103365 3.1601933285 4.1080134015 ZT12-15 4.8928585055 4.1487586279999995 5.636958383 ZT16-19 7.580696182 5.5928937874999995 9.5684985765 ZT20-23 17.558704095 14.822170024999998 20.295238165