condition mean min max ZT0-3 8.991678011166666 6.3725163049999995 11.610839717333334 ZT4-7 26.910585538333336 24.576562373333335 29.244608703333334 ZT8-11 68.02054207333333 48.37484328 87.66624086666667 ZT12-15 82.17982669 79.79601756 84.56363582 ZT16-19 37.86407984 25.73470618 49.9934535 ZT20-23 9.079088539499999 5.609693489 12.54848359