Purchasing power varies from state to state, as you probably know. For the rent on a small place in San Francisco, you can mortgage a huge home with acreage in Kentucky. The punchline is, “Yeah, but you’d have to live in Kentucky.” The Tax Foundation crunched the numbers and made a map, comparing how far $100 will go in purchasing power in each state compared with the national average. The map is above, but you can enlarge it at the site, and read about how it was compiled.
The immediate reaction from many was that the map is too simple. The cost of living in New York City is much higher than in the rest of New York state. That’s true- the bigger the city, the more expensive it is to live there. So the Tax Foundation created another map, with more detail to show metropolitan areas compared to their surrounding areas. See the interactive version at the site. In case you’re wondering, the most expensive city in the U.S. is Honolulu. -via mental_floss
For instance, while 7 states have zero income tax, uber-progressive (well progressive EXCEPT about Uber) California has a personal income tax that's, well, uber progressive -- varying from NEGATIVE (cash credits) to 13.3% -- by FAR the highest in the nation -- impossible to calculate in the formula.
Also ignored as impossible to calculate are fees, fines, and other state and local "non-purchase" levies by government. Fee-crazy California again "excels" in this area.
Hence the hypothetical $100 is AFTER-tax dollars. Other taxes included in a purchase (sales, excise, etc) ARE included in the comparison, but income tax is not. The REAL total difference between the states is often significantly higher as a result, but not included in this study.