condition mean min max ZT0-3 34.8827531675 31.74498755 38.020518785 ZT4-7 10.8945610535 6.871139040999999 14.917983066000001 ZT8-11 2.6254132114999997 2.0396730185 3.2111534044999996 ZT12-15 10.798904749250001 6.1387289785000005 15.45908052 ZT16-19 18.9547364975 16.83778059 21.071692405 ZT20-23 26.753415490000002 26.68180995 26.825021030000002