condition mean min max ZT0-3 13.81195 12.56785 15.056049999999999 ZT4-7 27.3976 27.3976 27.3976 ZT8-11 30.5974 30.5974 30.5974 ZT12-15 0 0 0 ZT16-19 30.0145 30.0145 30.0145 ZT20-23 23.9236 23.9236 23.9236