condition mean min max ZT0-3 4.330323333333333 1.22439 6.01007 ZT4-7 0.7532369999999999 0.7532369999999999 0.7532369999999999 ZT8-11 1.835035 1.835035 1.835035 ZT12-15 4.052745 4.027604999999999 4.077885 ZT16-19 4.768459999999999 4.768459999999999 4.768459999999999 ZT20-23 7.85805 7.85805 7.85805