condition mean min max ZT0-3 2.4976916666666664 1.8605550000000002 2.9755149999999997 ZT4-7 1.6065450000000001 1.6065450000000001 1.6065450000000001 ZT8-11 2.66452 2.66452 2.66452 ZT12-15 3.88812 3.474815 4.301425 ZT16-19 2.801005 2.801005 2.801005 ZT20-23 3.86149 3.86149 3.86149