The Kaiser Family Foundation is out Wednesday morning with a new look at what parts of the country stand to be affected the most by the health reform law’s insurance expansion. What you see above is every American zip code charted by the percent of its population that earns less than 400 percent of the Federal Poverty Line ($43,560 for an individual). That’s an important number: Anyone earning below it will either qualify for subsidized health insurance, and anyone earning less than 133 percent of the poverty line becomes eligible for Medicaid. Click through for an interactive version of the graphic, where you can search for specific zip codes.

The key takeaway, perhaps, is that the effects of health reform won’t be felt evenly across the country. Lower income Southern and rural areas stand to notice the impact of health reform a lot more, while more affluent areas, such as the Northeast, will see less of an effect.