If I'm reading this correctly, that is divorces per capita.
So, I'm calling BS on the whole study. If people don't get married, they can't get divorced. People in Alabama and Arkansas are simple more likely to get married, period. With a higher number of marriages you will naturally have a higher number of divorces. If you really want to look at the true state of marriage/divorce, the methodology needs to be divorces per marriage.
It would be an interesting study to look at the relationships of those who aren’t married but are living together.
However, if you take ONLY those who are married and compare them with each other, and one group is divorcing more than the other group, it’s not because of what non-marrieds are doing.
If I compare dogs in one area with dogs in another area, it doesn’t really matter what cats are doing.