condition mean min max ZT0-3 3.45 3.45 3.45 ZT4-7 31.9 31.9 31.9 ZT8-11 8.4 8.4 8.4 ZT12-15 4.0 4.0 4.0 ZT16-19 31.35 31.35 31.35 ZT20-23 14.05 14.05 14.05