condition mean min max ZT0-3 4.37993 2.545165 5.6119900000000005 ZT4-7 2.391105 2.391105 2.391105 ZT8-11 2.1544600000000003 2.1544600000000003 2.1544600000000003 ZT12-15 2.3374800000000002 2.06134 2.61362 ZT16-19 2.28857 2.28857 2.28857 ZT20-23 4.68721 4.68721 4.68721