condition mean min max ZT0-3 234.929129 234.929129 234.929129 ZT4-7 247.8474415 247.8474415 247.8474415 ZT8-11 247.758358 247.758358 247.758358 ZT12-15 259.3826445 259.3826445 259.3826445 ZT16-19 256.6458905 256.6458905 256.6458905 ZT20-23 230.567857 230.567857 230.567857