condition mean min max ZT0-3 168.616672 168.616672 168.616672 ZT4-7 168.7872985 168.7872985 168.7872985 ZT8-11 174.635696 174.635696 174.635696 ZT12-15 167.0108265 167.0108265 167.0108265 ZT16-19 161.845574 161.845574 161.845574 ZT20-23 179.3460095 179.3460095 179.3460095