US county map with bubbles

CDP Data Visualization Map visuals let you plot measurements, as bubbles, over US County regions. Bubble maps display up to two measurements simultaneously: as the color of the bubble, and as the relative size of the bubble.

A county map of the United States shows a comparison of measurement values across US States. The following steps extend the work completed in State map with bubbles and demonstrate how to create a map visual on the dataset US County Populations [data source samples.us_counties]. This produces a map with bubble marks that correspond to the total population of each county.

Clone the visual that you developed in Country map, choropleth.
For instructions, see Cloning a visual.
Under Dimensions, select ctyname and add it to the Geo shelf.
Click the field to open the Field Properties menu, expand the Change Type option, and select the Geo Type County.
Alias the field ctyname as County.
For instructions, see Alias.
If the Size shelf is empty, add a measure to it.
In this example the goal is to show the relative size of the Hispanic population across the country, so the following expression is used in the Enter/Edit Expression editor:
```
sum([h_female]+[h_male])
```
For more information, see Enter or edit expressions.
Optional: Alias all the fields.
For instructions, see Alias.
Optional: Change the color palette or simply reverse it, as described in Change color palette of visuals and Reverse color palette of visuals.
Click REFRESH VISUAL.
The map visual appears. Note that if you have Zoom enabled, the map automatically zooms in to show detail of California. For more information, see Customizing zoom.
Click the pencil/edit icon next to the title of the visualization to enter a name for the visual.

In this example, the title is changed to 'US County Population - Bubbles'. You can also add a brief description of the visual as a subtitle below the title of the visualization.
At the top left corner of the Dashboard Designer, click SAVE.