condition mean min max ZT0-3 3.13758897525 2.015270283 4.2599076675 ZT4-7 5.50568876275 4.555365924 6.4560116015 ZT8-11 4.942731639 4.314366273499999 5.5710970045 ZT12-15 3.115075332 2.86779104 3.3623596239999998 ZT16-19 4.76563596525 3.82245065 5.7088212805000005 ZT20-23 11.012490882 9.726376733999999 12.298605030000001