condition mean min max ZT0-3 239.533795 239.533795 239.533795 ZT4-7 233.0268545 233.0268545 233.0268545 ZT8-11 259.487866 259.487866 259.487866 ZT12-15 248.05306000000002 248.05306000000002 248.05306000000002 ZT16-19 262.840542 262.840542 262.840542 ZT20-23 225.0463245 225.0463245 225.0463245