Indeed, it's 41.2 million out of a total of 334.9 million U.S.-Americans, or 12.3 % or more than one in ten folks - that this is more than one in hundred suprised me because the US are by some counts the "richest" country on the planet.
It's merely the country with the richest few, perhaps this calculation is just a way to show statistically what many believed all along, namely that the so-called "American dream" is a pipe dream for most, in the sense that the majority of people simply fund a tiny fews success in the way lottery ticket buyers fund a few select millionaires that don't deserve it.