condition mean min max ZT0-3 30.383583333333334 26.2365 37.6058 ZT4-7 27.587699999999998 27.587699999999998 27.587699999999998 ZT8-11 18.360500000000002 18.360500000000002 18.360500000000002 ZT12-15 18.5977 16.9372 20.2582 ZT16-19 17.35905 17.35905 17.35905 ZT20-23 19.42275 19.42275 19.42275