condition mean min max ZT0-3 5.7108600685 5.5289862329999995 5.892733904 ZT4-7 4.324525921499999 3.5050633805 5.143988462499999 ZT8-11 4.78756992025 4.3482305335 5.226909307 ZT12-15 8.198143000249999 5.981011617 10.4152743835 ZT16-19 5.62184913275 5.4133126325 5.830385633000001 ZT20-23 7.6490737074999995 6.759423627 8.538723787999999