condition mean min max ZT0-3 0.7510063333333333 0.466366 1.0683795 ZT4-7 0.548832 0.548832 0.548832 ZT8-11 2.32533 2.32533 2.32533 ZT12-15 2.9737225 2.311145 3.6363000000000003 ZT16-19 2.051825 2.051825 2.051825 ZT20-23 1.39086 1.39086 1.39086