condition mean min max ZT0-3 1.0487985 0.47493699999999994 1.62266 ZT4-7 0.7490490000000001 0.7490490000000001 0.7490490000000001 ZT8-11 1.3949685 1.3949685 1.3949685 ZT12-15 0 0 0 ZT16-19 0.740127 0.740127 0.740127 ZT20-23 0.531625 0.531625 0.531625