condition mean min max ZT0-3 0.6233883333333333 0.0 1.870165 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 0.83651 0.0 1.67302 ZT16-19 0.0 0.0 0.0 ZT20-23 1.806825 1.806825 1.806825