condition mean min max ZT0-3 5.5409925 5.18085 5.901135 ZT4-7 2.184265 2.184265 2.184265 ZT8-11 0.538935 0.538935 0.538935 ZT12-15 0 0 0 ZT16-19 3.21425 3.21425 3.21425 ZT20-23 4.578335 4.578335 4.578335