condition mean min max ZT0-3 6.634141604 6.574475835 6.693807372999999 ZT4-7 4.92154065075 4.349084459 5.4939968425 ZT8-11 8.72437980825 5.655641931 11.7931176855 ZT12-15 11.290444963999999 10.560718098999999 12.020171828999999 ZT16-19 7.6066214975 7.2752989105 7.9379440845 ZT20-23 9.60011594525 9.3408764315 9.859355459