condition mean min max ZT0-3 11.07433 6.995255 14.05749 ZT4-7 15.46895 15.46895 15.46895 ZT8-11 18.877499999999998 18.877499999999998 18.877499999999998 ZT12-15 47.16765 31.6494 62.685900000000004 ZT16-19 32.74705 32.74705 32.74705 ZT20-23 16.5953 16.5953 16.5953