condition mean min max ZT0-3 11.260095 10.73929 11.780899999999999 ZT4-7 15.36185 15.36185 15.36185 ZT8-11 18.24715 18.24715 18.24715 ZT12-15 0 0 0 ZT16-19 15.431049999999999 15.431049999999999 15.431049999999999 ZT20-23 13.8921 13.8921 13.8921