condition mean min max ZT0-3 1.64482 1.64482 1.64482 ZT4-7 0.735409 0.735409 0.735409 ZT8-11 0.23811549999999998 0.23811549999999998 0.23811549999999998 ZT12-15 1.372115 1.372115 1.372115 ZT16-19 5.52059 5.52059 5.52059 ZT20-23 3.32879 3.32879 3.32879