condition mean min max ZT0-3 8.45 8.45 8.45 ZT4-7 1.5 1.5 1.5 ZT8-11 3.1 3.1 3.1 ZT12-15 2.6 2.6 2.6 ZT16-19 3.25 3.25 3.25 ZT20-23 4.85 4.85 4.85