condition mean min max ZT0-3 2.630865 2.515315 2.746415 ZT4-7 1.34264 1.34264 1.34264 ZT8-11 1.81241 1.81241 1.81241 ZT12-15 0 0 0 ZT16-19 3.529115 3.529115 3.529115 ZT20-23 3.017375 3.017375 3.017375