Because the entire country is relatively rich. In fact, America’s bottom ventile is still richer than most of the world http://tinyurl.com/63n24wa

That is, the typical person in the bottom 5 percent of the American income distribution is still richer than 68 percent of the world’s inhabitants. http://tinyurl.com/63n24wa

I had this letter sent to me over Twitter. I do not know who did it or how long it has been out here.