condition mean min max ZT0-3 401.475917 401.475917 401.475917 ZT4-7 421.7291945 421.7291945 421.7291945 ZT8-11 325.2005755 325.2005755 325.2005755 ZT12-15 397.3429005 397.3429005 397.3429005 ZT16-19 396.3425955 396.3425955 396.3425955 ZT20-23 365.84817150000003 365.84817150000003 365.84817150000003