condition mean min max ZT0-3 17.58127 17.58127 17.58127 ZT4-7 22.0233725 22.0233725 22.0233725 ZT8-11 20.067494 20.067494 20.067494 ZT12-15 17.601801000000002 17.601801000000002 17.601801000000002 ZT16-19 17.2161965 17.2161965 17.2161965 ZT20-23 28.0681205 28.0681205 28.0681205