condition mean min max ZT0-3 5.033365 4.885695 5.181035 ZT4-7 6.03327 6.03327 6.03327 ZT8-11 4.643735 4.643735 4.643735 ZT12-15 0 0 0 ZT16-19 5.538945 5.538945 5.538945 ZT20-23 4.82765 4.82765 4.82765