condition mean min max ZT0-3 5.272425 5.272425 5.272425 ZT4-7 17.83445 17.83445 17.83445 ZT8-11 12.750599999999999 12.750599999999999 12.750599999999999 ZT12-15 4.91301 4.91301 4.91301 ZT16-19 0.23048380000000002 0.23048380000000002 0.23048380000000002 ZT20-23 0.526937 0.526937 0.526937