condition mean min max ZT0-3 1.6 1.6 1.6 ZT4-7 1.3 1.3 1.3 ZT8-11 2.65 2.65 2.65 ZT12-15 2.95 2.95 2.95 ZT16-19 1.4500000000000002 1.4500000000000002 1.4500000000000002 ZT20-23 2.65 2.65 2.65