condition mean min max ZT0-3 8.380045 8.380045 8.380045 ZT4-7 7.40158 7.40158 7.40158 ZT8-11 4.565765000000001 4.565765000000001 4.565765000000001 ZT12-15 5.934480000000001 5.934480000000001 5.934480000000001 ZT16-19 12.026895 12.026895 12.026895 ZT20-23 5.053929999999999 5.053929999999999 5.053929999999999