condition mean min max ZT0-3 0.036598983333333335 0.021642966666666666 0.051555 ZT4-7 0.0554839 0.0554839 0.0554839 ZT8-11 0.0194028 0.0194028 0.0194028 ZT12-15 0.035113425 0.0 0.07022685 ZT16-19 0.01069514 0.0 0.02139028 ZT20-23 0 0 0