condition mean min max ZT0-3 6.0 6.0 6.0 ZT4-7 1.9 1.9 1.9 ZT8-11 44.5 44.5 44.5 ZT12-15 5.8 5.8 5.8 ZT16-19 1.45 1.45 1.45 ZT20-23 17.35 17.35 17.35