condition mean min max ZT0-3 1.9038633333333332 1.58768 2.29766 ZT4-7 1.91625 1.91625 1.91625 ZT8-11 1.4892150000000002 1.4892150000000002 1.4892150000000002 ZT12-15 2.9054200000000003 2.75475 3.05609 ZT16-19 1.960995 1.960995 1.960995 ZT20-23 2.50785 2.50785 2.50785