condition mean min max ZT0-3 4.5 4.5 4.5 ZT4-7 1.0 1.0 1.0 ZT8-11 4.1 4.1 4.1 ZT12-15 0.95 0.95 0.95 ZT16-19 3.8 3.8 3.8 ZT20-23 2.25 2.25 2.25