condition mean min max ZT0-3 9.135892 9.135892 9.135892 ZT4-7 9.580948 9.580948 9.580948 ZT8-11 10.042826999999999 10.042826999999999 10.042826999999999 ZT12-15 10.5794475 10.5794475 10.5794475 ZT16-19 9.4132355 9.4132355 9.4132355 ZT20-23 8.530620500000001 8.530620500000001 8.530620500000001