condition mean min max ZT0-3 5.7317141215 3.504570965 7.958857277999999 ZT4-7 2.63867647425 2.291065972 2.9862869764999997 ZT8-11 2.803241684 2.389617189 3.216866179 ZT12-15 3.5769063127500003 2.9304610585 4.223351567 ZT16-19 5.93985817375 4.5870534595 7.292662888000001 ZT20-23 9.900683497 8.635985024 11.165381969999999