Interactive drill up and down geographical hierarchies on a Choropleth Map in Microsoft Excel
The post Faster Choropleth Maps with Microsoft Excel provided a faster version to update a Choropleth Map in Microsoft Excel. The approach made it possible to use Choropleth Maps with several thousand regions on an interactive Microsoft Excel dashboard in production.
This also opened up new possibilities to enhance the maps with additional features. Leonid Koyfman contributed a couple of great enhancements in the follow-up article Fast Choropleth Map with Enhanced Features like filtering the data by value bin, showing tooltips and letting the user decide whether the map shall be colored by state or by county.
Very soon after this follow-up article was published, Leonid came up with another great idea. He suggested to take the user selection of how to color the map to the next level: let the user easily drill up and down the geographical hierarchy by simply clicking on the map. One click toggles from coloring the entire state to the counties in that state and vice versa. I have to admit, I am sitting on this nugget for one and half years already and never found (well, more precisely never took) the time to publish it. But finally the time has come. Here it is.
Today’s article explains Leonid’s idea and implementation how to drill up and down geographical hierarchies on a Microsoft Excel Choropleth Map.
The article includes two example workbooks for free download: the USA by states and counties and Germany by the two common ZIP-code levels PLZ2 and PLZ5 (first two digits of the ZIP-code and the entire five digits ZIP-code).