condition mean min max ZT0-3 0.0671166 0.0668732 0.06736 ZT4-7 0.0 0.0 0.0 ZT8-11 0.06805665 0.06805665 0.06805665 ZT12-15 0 0 0 ZT16-19 0.0496602 0.0496602 0.0496602 ZT20-23 0.0 0.0 0.0