condition mean min max ZT0-3 0.04498616666666666 0.0145759 0.0749772 ZT4-7 0.0 0.0 0.0 ZT8-11 0.044965000000000005 0.044965000000000005 0.044965000000000005 ZT12-15 0.123795025 0.1100835 0.13750655 ZT16-19 0.1139915 0.1139915 0.1139915 ZT20-23 0.08007734999999999 0.08007734999999999 0.08007734999999999