condition mean min max ZT0-3 1880.811127 1880.811127 1880.811127 ZT4-7 1932.0488785 1932.0488785 1932.0488785 ZT8-11 2098.195256 2098.195256 2098.195256 ZT12-15 1842.054328 1842.054328 1842.054328 ZT16-19 1961.913001 1961.913001 1961.913001 ZT20-23 1925.0436285 1925.0436285 1925.0436285