condition mean min max ZT0-3 0.953765 0.953765 0.953765 ZT4-7 0.5094535 0.5094535 0.5094535 ZT8-11 0.443601 0.443601 0.443601 ZT12-15 0.9889645 0.9889645 0.9889645 ZT16-19 2.41298 2.41298 2.41298 ZT20-23 1.30755 1.30755 1.30755