Where’s the Local Big Mac Price Data?

Every now and then I indulge in a Big Mac meal from McDonald's. I feel satisfied while I eat the burger and fries and suck down my diet soda, but afterwards I feel sleepy, sluggish, and fat. Today was one of those days.

As I ate my my satisfying-not-so-satisfying meal, I wondered what the Big Mac price differences from state to state or even city to city. I know that there's data going around about Big Mac prices in different countries, but I'm pretty sure it varies quite a bit in the U.S. alone. I don't remember paying over $6 for the number 1 in California. What a jip (and yet I've been to the golden arches at least three times in the past month).