condition mean min max ZT0-3 2.3496125 2.14723 2.551995 ZT4-7 7.33779 7.33779 7.33779 ZT8-11 18.9687 18.9687 18.9687 ZT12-15 0 0 0 ZT16-19 7.94486 7.94486 7.94486 ZT20-23 4.77793 4.77793 4.77793