condition mean min max ZT0-3 1.3 1.3 1.3 ZT4-7 1.2 1.2 1.2 ZT8-11 17.8 17.8 17.8 ZT12-15 1.65 1.65 1.65 ZT16-19 1.85 1.85 1.85 ZT20-23 1.85 1.85 1.85