condition mean min max ZT0-3 2.986155 2.986155 2.986155 ZT4-7 6.16015 6.16015 6.16015 ZT8-11 2.51765 2.51765 2.51765 ZT12-15 1.9007399999999999 1.9007399999999999 1.9007399999999999 ZT16-19 2.6240449999999997 2.6240449999999997 2.6240449999999997 ZT20-23 1.9436 1.9436 1.9436