Cariann sent over this Pop vs Soda map. It’s based on a survey where people first say where they’re from, and are then asked to describe what term they use to describe pop (or soda, Coke, etc).

Pop vs Soda Soft Drink Survey

I imagine people tend to use the term they grew up with except when it’s a burden to stick with your roots after relocating to a different area of the country where people think you’re weird for calling pop “pop.”