condition mean min max ZT0-3 16.9 16.9 16.9 ZT4-7 26.0 26.0 26.0 ZT8-11 8.75 8.75 8.75 ZT12-15 3.55 3.55 3.55 ZT16-19 3.4 3.4 3.4 ZT20-23 13.85 13.85 13.85