Choropleth Maps

This is a Choropleth Map which shows the use of domestic freshwater including withdrawals and deliveries in 1990. A choropleth map is a thematic map in which areas are shaded or patterned in proportion to the measurement of the statistical variable being displayed on the map. A choropleth map provides and easy way to visualize how a measurement varies across a geographic area or it shows the level of variability within a region. As seen from the map above most of the freshwater use in 1990 came from the states that are by the water including Florida, California, Texas, Illinois, and New York. Most of the north western part of the United States used little amounts of freshwater while Vermont and Alaska used the least of all of them.

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