Have you run into this problem: you have a list of phone numbers and associated values which would be best shown geographically to see patterns, but there isn’t a clear way to put the data on a map. Maybe you’d like to see a map of customer service calls by call duration or inbound sales by average order size.
I wanted to share how to MacGyver a solution with a piece of twine, bubble gum, Excel, and a free online map tool. To me, this is a nice testament to the simple but powerful data visualizations that can be accomplished without programming skills or expensive applications.
1. Pull out area codes
First I pulled the area codes from my list of phone numbers using the formula below. This simply checks if the phone number starts with 1, then grabs the appropriate three digits for the area code.
2. Convert area codes into states
For my purposes, mapping the phone numbers by state was sufficient. Ideally, we would map the phone numbers to precise latitude and longitude coordinates by doing a reverse lookup of addresses then using the Excel geocoding tool.
First I needed a lookup table that could link my list of area codes to states. I wasn’t able to track down a good data table, so I grabbed the data from All Area Codes and cleaned it up. Here is a lookup table of area codes by state.
An aside: I have a pet peeve with people who sell data that feels like it should be publicly available. You’ll run across these businesses when looking for basic information about ZIP codes, MSAs, or area codes. Here is an example of one of these parasitic businesses.
3. Create your summary data set
I used a pivot table to summarize metrics by state.
4. Create colorized map of the US
Our friend Ducky Sherwood has generously put together a online tool called Mapeteria that will generate a colorized overlay of US states. In Ducky’s words: "Want to make a choropleth thematic map (i.e. coloured based on your data) for Canadian provinces, U.S. states, or French dÃ©partements?" This overlay can be viewed in either Google Maps or Google Earth.
Here’s where it gets a little tricky. You will need to provide Mapeteria with a URL to a properly structured CSV file. Posting a CSV file to a web server isn’t trivial if you aren’t running your own web site. I found one free service called FileDEN that did the job (other suggestions?). Beware all the advertising—and in all likelihood they immediately sold my e-mail address at registration. Nevertheless, you can upload a file here and it will give you a URL which can be used to create your map.
Here’s an example of the results: