condition mean min max ZT0-3 1.4524615 0.7668595 1.918425 ZT4-7 0.730842 0.730842 0.730842 ZT8-11 0.7502504999999999 0.7502504999999999 0.7502504999999999 ZT12-15 1.01798325 0.8390215000000001 1.196945 ZT16-19 1.16176 1.16176 1.16176 ZT20-23 1.9094799999999998 1.9094799999999998 1.9094799999999998