condition mean min max ZT0-3 1.1737561666666667 0.8649495 1.58436 ZT4-7 0.5255425 0.5255425 0.5255425 ZT8-11 0.9419789999999999 0.9419789999999999 0.9419789999999999 ZT12-15 2.16148 2.081455 2.241505 ZT16-19 4.09229 4.09229 4.09229 ZT20-23 3.02259 3.02259 3.02259