condition mean min max ZT0-3 4.149214838000001 3.692299662 4.6061300140000005 ZT4-7 3.9906389325000005 3.523008039 4.458269826 ZT8-11 3.3803030394999998 2.6429515849999996 4.117654494 ZT12-15 3.6766815028333335 3.591777203 3.7615858026666666 ZT16-19 4.7053199999999995 4.042818303333333 5.367821696666666 ZT20-23 5.371290430666667 4.893543187000001 5.849037674333333