condition mean min max ZT0-3 2.0382775 1.807965 2.2685899999999997 ZT4-7 2.8166599999999997 2.8166599999999997 2.8166599999999997 ZT8-11 1.89407 1.89407 1.89407 ZT12-15 0 0 0 ZT16-19 2.35862 2.35862 2.35862 ZT20-23 2.004635 2.004635 2.004635