condition mean min max ZT0-3 8.609774970416668 7.678727652333333 9.540822288500001 ZT4-7 6.256053957000001 6.112290286333334 6.399817627666667 ZT8-11 5.278601100166666 4.376081080333333 6.18112112 ZT12-15 4.635784020166667 4.434140137666667 4.837427902666667 ZT16-19 5.6676852075 5.5309227430000005 5.804447672 ZT20-23 6.512939533 6.3341315719999995 6.691747494