condition mean min max ZT0-3 2.60104575 2.5757015 2.62639 ZT4-7 0.9650934999999999 0.9650934999999999 0.9650934999999999 ZT8-11 4.598599999999999 4.598599999999999 4.598599999999999 ZT12-15 0 0 0 ZT16-19 4.4620999999999995 4.4620999999999995 4.4620999999999995 ZT20-23 6.142665 6.142665 6.142665