Unclassified Choropleth Map - Fertility

http://www.esds.ac.uk/international/support/user_guides/gisoverview.asp

There are several types of choropleth maps. This particular type is called an unclassified choropleth map. It's similar to other choropleth maps as it uses different shading of colors to represent data, but in this case the data is not areally averaged into specific intervals. However, because of that fact, it might be more useful than classified choropleth maps because color shades are directly proportional to each numerical value, and so it shows a wide variety of shading that represents the diversity of the data (rather than classifying it into large intervals). The diagram above shows the fertility rate in various countries of Europe. The darkest shade of orange represents the maximum fertility, while the lightest shade shows the least fertility.