condition mean min max ZT0-3 3.948945 3.948945 3.948945 ZT4-7 3.680955 3.680955 3.680955 ZT8-11 4.458565 4.458565 4.458565 ZT12-15 4.3003 4.3003 4.3003 ZT16-19 5.36829 5.36829 5.36829 ZT20-23 3.55076 3.55076 3.55076