More than 80% of American states are home to at least one of 623 billionaires—including some non-U.S. citizens. : If this is your first time registering, please check your inbox for more information about the benefits of your Forbes account and what you can do next! More than 80% of American states are home to at least one of 623 billionaires—including some non-U.S. citizens. Even as the stock market faltered amid coronavirus concerns, the United States still leads the world in the number of billionaires who call the country their home.