condition mean min max ZT0-3 2.1316249999999997 2.1316249999999997 2.1316249999999997 ZT4-7 1.08689 1.08689 1.08689 ZT8-11 1.883915 1.883915 1.883915 ZT12-15 4.007820000000001 4.007820000000001 4.007820000000001 ZT16-19 4.92929 4.92929 4.92929 ZT20-23 4.83988 4.83988 4.83988