condition mean min max ZT0-3 7.492001666666667 4.79321 10.43923 ZT4-7 6.568910000000001 6.568910000000001 6.568910000000001 ZT8-11 4.1354299999999995 4.1354299999999995 4.1354299999999995 ZT12-15 4.6548775 4.0733950000000005 5.2363599999999995 ZT16-19 5.348155 5.348155 5.348155 ZT20-23 11.7604 11.7604 11.7604