Choropleth

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This is a choropleth map that uses a graduated color scheme to indicate changes in population for the state of Wisconsin. A single-hue color scheme is used in the upper two maps to indicate population density in Wisconsin for the years 1970 and 2000.

The lower map uses a bi-polar color scheme to indicate the percent change in Wisconsin population from the years 1970 to 2000. A red hue progression is used to indicate a negative percent change while a blue hue progression is used to indicate a positive percent change.

The projection I used is the North America Albers Equal Area Conic. I used this projection to maintain area of the maps so I could calculate the correct area for each of the counties.