condition mean min max ZT0-3 3.67375 3.0307399999999998 4.31676 ZT4-7 6.874700000000001 6.874700000000001 6.874700000000001 ZT8-11 2.7287850000000002 2.7287850000000002 2.7287850000000002 ZT12-15 0 0 0 ZT16-19 3.90787 3.90787 3.90787 ZT20-23 5.84274 5.84274 5.84274