This image is a self-generated thematic map from the <a href="https://en.wikipedia.org/wiki/U.S._Census_Bureau" class="extiw" title="en:U.S. Census Bureau">en:U.S. Census Bureau</a>'s American Factfinder at <a rel="nofollow" class="external free" href="http://factfinder.census.gov/">http://factfinder.census.gov/</a> by Wikipedia user <a href="https://en.wikipedia.org/wiki/User:Stevey7788" class="extiw" title="en:User:Stevey7788">Stevey7788</a>.<br><b>This map does not</b> keep a map key and thus there only be drawn relative conclusions from the depicted colors: Dark red supposedly shows higher concentrations than light yellow, that is about it.
User <a href="https://en.wikipedia.org/wiki/User:Stevey7788" class="extiw" title="en:User:Stevey7788">Stevey7788</a> on <a class="external text" href="https://en.wikipedia.org">en.wikipedia</a>
<span class="int-own-work" lang="en">Own work</span>