condition mean min max ZT0-3 4.1067125 3.475855 4.73757 ZT4-7 3.189615 3.189615 3.189615 ZT8-11 2.92227 2.92227 2.92227 ZT12-15 0 0 0 ZT16-19 4.00121 4.00121 4.00121 ZT20-23 4.409695 4.409695 4.409695