condition mean min max ZT0-3 3.311710199 0.44352765 6.179892748 ZT4-7 37.723202525000005 24.657282035 50.789123015 ZT8-11 59.65516868 57.78022333 61.53011403 ZT12-15 25.819902685 14.40501124 37.23479413 ZT16-19 6.82498618675 5.174537868 8.4754345055 ZT20-23 1.5590824735 1.207328634 1.910836313