Clarification on Sonic locations

So, in my previous post, I implied that Sonic Drive-In restaurants are primarily a Southwestern phenomenon. On twitter, @ElenaMorning pointed out that they have Sonic in the East and in the Midwest.

Fortunately, here comes . . .

Science!™ to the rescue!

Using data from the Sonic website, and the 2010 census numbers, I have calculated the number of Sonics per million people in each state. (To be fair, "calculated" overstates things a bit.) The pattern is centered on Oklahoma and Arkansas, and reaches much farther east than I had realized. So, it is perhaps better characterized as a south-central phenomenon. My apologies and respect to @ElenaMorning.

Here's a visualization, created using Targetmap:

Feel free to refer to this map when deciding where to live next.