condition mean min max ZT0-3 234.693595 234.693595 234.693595 ZT4-7 276.5106175 276.5106175 276.5106175 ZT8-11 256.618564 256.618564 256.618564 ZT12-15 300.015905 300.015905 300.015905 ZT16-19 221.624494 221.624494 221.624494 ZT20-23 164.86638349999998 164.86638349999998 164.86638349999998