condition mean min max ZT0-3 10.9636375 10.876175 11.0511 ZT4-7 11.358550000000001 11.358550000000001 11.358550000000001 ZT8-11 15.85945 15.85945 15.85945 ZT12-15 0 0 0 ZT16-19 12.26585 12.26585 12.26585 ZT20-23 13.58995 13.58995 13.58995