condition mean min max ZT0-3 1.171234 0.819158 1.52331 ZT4-7 4.616935 4.616935 4.616935 ZT8-11 6.841695 6.841695 6.841695 ZT12-15 0 0 0 ZT16-19 4.205075 4.205075 4.205075 ZT20-23 1.9757799999999999 1.9757799999999999 1.9757799999999999