condition mean min max ZT0-3 16.548125 14.23825 18.858 ZT4-7 21.14645 21.14645 21.14645 ZT8-11 4.887285 4.887285 4.887285 ZT12-15 0 0 0 ZT16-19 9.730445 9.730445 9.730445 ZT20-23 17.204549999999998 17.204549999999998 17.204549999999998