condition mean min max ZT0-3 8.564738981083334 7.663503758666667 9.4659742035 ZT4-7 9.001957703999999 8.802807149333333 9.201108258666666 ZT8-11 11.057871986166667 11.048533300333334 11.067210672 ZT12-15 11.33837608 10.09154571 12.58520645 ZT16-19 11.678408986 10.885920408666667 12.470897563333333 ZT20-23 14.0650284255 12.036320621 16.093736229999998