condition mean min max ZT0-3 2.2241825 1.75678 2.691585 ZT4-7 1.0706765 1.0706765 1.0706765 ZT8-11 1.477445 1.477445 1.477445 ZT12-15 0 0 0 ZT16-19 1.864265 1.864265 1.864265 ZT20-23 2.236585 2.236585 2.236585