Domestic migration has changed over the past 10 years, as Americans chase better jobs, cheaper housing and a greater quality of life wherever they can find it.

As of Monday, 18 states and one territory, including California, Pennsylvania, Michigan and Puerto Rico, no longer have residency requirements. Check the map below to see if your state is on the list.

The map, which has been around for a while, has a lot of explanatory power when it comes to America's position in the global economy. For each state, Perry finds a country that had a roughly ...