Unstandardized Choropleth map

The above image is an example of an unstandardized choropleth map.  This type of map is useful to display statistics for a large area like a state or country.  However, it is not always representative of the more local levels of populations, like counties or towns.  This map shows the percent change of the population of each state.  Its visualizatition method is displaying statistics through color.
http://www.census.gov/population/www/pop-profile/sttrend.html