The study, titled “Them Vs. U.S,” defined the American “elite” as “having a postgraduate degree, a household income of more than $150,000 annually, and living in a zip code with more than 10,000 people per square mile.” Such people account for about 1 percent of Americans. The study also examined a sub-sample of the 1 percent who graduated from Ivy League schools or other name-brand institutions such as Northwestern, Duke, Stanford, and the University of Chicago.