To compare and contrast historical definitions, visit our interactive ArcGIS
On ArcGIS, click on “Content” (top left side, middle icon). When the list of maps finishes loading, check the box(es) for the map(s) you would like to view.
To view dynamic maps individually, click on the “View in ArcGIS” links below.
Click on the map name in the chart below to read a description of the definition and view original map. From each individual map page you can access the names of counties included in the definition and access the relevant ArcGIS shape files
