condition mean min max ZT0-3 19.9 19.9 19.9 ZT4-7 81.6 81.6 81.6 ZT8-11 41.35 41.35 41.35 ZT12-15 33.15 33.15 33.15 ZT16-19 69.75 69.75 69.75 ZT20-23 56.45 56.45 56.45