condition mean min max ZT0-3 21.0 21.0 21.0 ZT4-7 12.4 12.4 12.4 ZT8-11 33.0 33.0 33.0 ZT12-15 27.85 27.85 27.85 ZT16-19 24.75 24.75 24.75 ZT20-23 24.9 24.9 24.9