condition mean min max ZT0-3 0.6401133333333333 0.42943149999999997 0.9556295 ZT4-7 0.632649 0.632649 0.632649 ZT8-11 1.3760949999999998 1.3760949999999998 1.3760949999999998 ZT12-15 1.8892300000000002 1.7334450000000001 2.0450150000000002 ZT16-19 2.16571 2.16571 2.16571 ZT20-23 1.638425 1.638425 1.638425