DC: The highest concentration of "rich people"?

Highest concentration of "One Percenters"  in the U.S. are in the DC metro-area (surpassing NY, Los Angeles, Silicon Valley).

http://www.stltoday.com/news/national/govt-and-politics/d-c-awash-in-contracts-lobbying-wealth/article_53336d9b-a75f-5a1a-bb19-d46d3186a960.html