condition mean min max ZT0-3 7.55 7.55 7.55 ZT4-7 1.6 1.6 1.6 ZT8-11 15.05 15.05 15.05 ZT12-15 1.2 1.2 1.2 ZT16-19 7.75 7.75 7.75 ZT20-23 24.75 24.75 24.75