condition mean min max ZT0-3 3.15058916825 2.9639882280000003 3.3371901084999998 ZT4-7 5.73264322925 4.846115754 6.6191707045 ZT8-11 8.064915 6.357360726 9.772469273999999 ZT12-15 8.40528085875 7.946290638999999 8.8642710785 ZT16-19 8.92599764875 8.869014445000001 8.982980852499999 ZT20-23 10.837711845000001 10.704218405 10.971205285