condition mean min max ZT0-3 0.0 0.0 0.0 ZT4-7 0.0209659575 0.0 0.041931915 ZT8-11 0.0088854305 0.0 0.017770861 ZT12-15 0.0 0.0 0.0 ZT16-19 0.011265175833333333 0.0 0.022530351666666667 ZT20-23 0.0 0.0 0.0