condition mean min max ZT0-3 21.744950000000003 21.744950000000003 21.744950000000003 ZT4-7 17.378999999999998 17.378999999999998 17.378999999999998 ZT8-11 16.4122 16.4122 16.4122 ZT12-15 18.6722 18.6722 18.6722 ZT16-19 20.73365 20.73365 20.73365 ZT20-23 24.0262 24.0262 24.0262