condition mean min max ZT0-3 0.877336 0.847907 0.906765 ZT4-7 1.33539 1.33539 1.33539 ZT8-11 1.6608695 1.6608695 1.6608695 ZT12-15 0 0 0 ZT16-19 0.891926 0.891926 0.891926 ZT20-23 1.5594264999999998 1.5594264999999998 1.5594264999999998