It show the 25 states that have refused to implement the Medicaid expansion provisions of "ObamaCare" and the number of people who are, as a result, still going to be without adequate health care. It's about 5 million people.
It boggles the mind to imagine that this is a sustainable political position, but that is another question.
Non-cooperation with Obamacare's Medicaid expansion is one of the tactics that the Republican Party has adopted, so the map is close to the political map of the USA -- the familiar L Shape of a solid GOP South and then a vertical slice up the plains and mountain as well.
The slave economy of the South made all of the consumption done by the slaves a direct expense of the slaveowners. The slaveowners could control the quality and quantity of food, clothes and housing that the slaves used. There was no return from those expenses except the bodily continuation of the slaves and their families.
The wage labor system elsewhere put cash in the hands of workers, who then spent the cash. That money circulated.
One of the legacies of slavery is that there is a whole section of the country which assumes that wages and benefits given to those who work, and consequently those not working, should be minimized to the greatest extent possible.
As soon as the Supreme Court said that states did not have to extend Medicaid to the working poor, those states took the opportunity to minimize another benefit to their workers. That benefit would disrupt the whole low-wage, low-benefit economy of the region.
Whenever a federal program is implemented and administered by the states, the program will end up reinforcing the local systems of exploitation and oppression. And that is usually the price of getting legislation through Congress. Very few programs have benefit levels not set by the state: Social Security is one, although workers in low wage states will have contributed less over their working life and will therefore receive a lower benefit, no matter where they live.
"Federalism" is a crucial institution that makes up institutionalized racism. Although it appears "race neutral" and motivated by the high principles of "decentralized democracy" and "local control", it reinforces racial inequality and empowers disproportionately those who lead local systems most successful in subjugating African Americans and other populations of color.