condition mean min max ZT0-3 5.653430333333334 5.653430333333334 5.653430333333334 ZT4-7 5.455694 5.455694 5.455694 ZT8-11 2.879654 2.879654 2.879654 ZT12-15 3.842339 3.842339 3.842339 ZT16-19 2.8207739999999997 2.8207739999999997 2.8207739999999997 ZT20-23 4.748688 4.748688 4.748688