condition mean min max ZT0-3 113.693595 113.693595 113.693595 ZT4-7 168.692296 168.692296 168.692296 ZT8-11 185.053649 185.053649 185.053649 ZT12-15 162.0912815 162.0912815 162.0912815 ZT16-19 138.76703099999997 138.76703099999997 138.76703099999997 ZT20-23 119.26607949999999 119.26607949999999 119.26607949999999