condition mean min max ZT0-3 51.6085811775 49.035710885 54.18145147 ZT4-7 33.9509206075 30.78717829 37.114662925000005 ZT8-11 60.193700755 44.68115007 75.70625144 ZT12-15 67.5021704375 60.861096465 74.14324441 ZT16-19 57.606095620000005 53.276543005 61.935648235 ZT20-23 52.444976945 51.36996775 53.51998614