condition mean min max ZT0-3 5.38403587775 4.12554157 6.6425301855 ZT4-7 10.47976150425 9.8884574185 11.07106559 ZT8-11 9.483560087 9.432643289 9.534476885 ZT12-15 27.5452822675 24.624475175 30.466089359999998 ZT16-19 31.0527515725 30.186764965000002 31.91873818 ZT20-23 45.460860935 43.59739382 47.324328050000005