This is a heatmap of every single community pharmacy in the United States. As the colors change from green to yellow to red the concentration of pharmacies is higher. It is clear to see that the number of pharmacies in an area correlates to the population density.
How it was Made
As far as i know there is no freely accessible directory of pharmacies in the United States. Using different resources available on the internet I wrote a few datascraping and screenscraping scripts in python to scour the internet. After letting the scripts run for a few days, i found about 59,000 locations across the country which correlated well with the NACDS estimate.
Now, with a database of every pharmacy and address i used the Google Geocoding API and the Yahoo! Maps Geocoding API to convert the addresses to latitude and longitude points. Next, using the Google Maps API i loaded all the datapoints to create this image. The wonderful thing about this map is the fact that you can zoom all the way down to the precise location of any pharmacy in the United States.
I hope that by the time i am done with tools they will help independent pharmacists make better decisions on where to open stores or to reach out to patients in areas where pharmacists are not accessible.