condition mean min max ZT0-3 3.15 3.15 3.15 ZT4-7 1.0 1.0 1.0 ZT8-11 6.3999999999999995 6.3999999999999995 6.3999999999999995 ZT12-15 2.7 2.7 2.7 ZT16-19 1.7000000000000002 1.7000000000000002 1.7000000000000002 ZT20-23 1.9 1.9 1.9