condition mean min max ZT0-3 1.094642 1.082674 1.10661 ZT4-7 0.9587669999999999 0.9587669999999999 0.9587669999999999 ZT8-11 2.152155 2.152155 2.152155 ZT12-15 0 0 0 ZT16-19 2.190035 2.190035 2.190035 ZT20-23 1.63581 1.63581 1.63581