condition mean min max ZT0-3 2.8593919999999997 1.644001 4.641565 ZT4-7 1.126188852945 1.126188852945 1.126188852945 ZT8-11 1.6731715 1.6731715 1.6731715 ZT12-15 2.9103425 2.000135 3.82055 ZT16-19 2.1427425 2.1427425 2.1427425 ZT20-23 5.750425 5.750425 5.750425