condition mean min max ZT0-3 17.655603 17.655603 17.655603 ZT4-7 18.713041500000003 18.713041500000003 18.713041500000003 ZT8-11 17.227894 17.227894 17.227894 ZT12-15 16.937000500000003 16.937000500000003 16.937000500000003 ZT16-19 16.466076 16.466076 16.466076 ZT20-23 32.8357445 32.8357445 32.8357445