The first column, "Brain Drain Rank," ranks this migration process based on two measures. The primary ranking is the positive vs negative flows. If more educated people are moving into a state than leaving it (+/+), it has a higher rank. If more poorly educated people are moving into a state than leaving (-/-), it has a lower rank. The lowest rank in this list is for states who not only have negative migration of highly educated people, but have positive migration of poorly educated people--meaning that people with college degrees are leaving the state, while people with only a high school degree or less are coming into that state. Thus, a state could have a net gain of people moving into a state, but that gain comes entirely from poorly educated people.
Data indicates that there is a strong relationship between education and employment. People with college degrees have a far higher likelihood of finding jobs compared to people who only have a high school diploma or less. Further, those jobs tend to pay far more. Thus, an net in-flow into a state of people with only a high-school degree (or less), means that state could face greater demands on its social services budgets due to higher rates of unemployment of its residents, while a net out-flow of people with college degrees can mean there are fewer resources to increase the tax base and social service providers. On the one hand, it is of course problematic for a state to have net losses of a population--"dying states," as such--for example, Alabama, Kansas and Kentucky, who lost both the highly educated and the poorly educated in 2014. On the other hand, it becomes an even greater problem for a state's economy when the highly educated are leaving, but the poorly educated are moving in.
Indiana ranks the worst in this combined measure--states who lost people with college degrees, but gained people with only a high school education or less. Indiana had the highest rate of loss of college graduates. Six states had higher rates of loss of college graduates--New Jersey, Illinois, South Dakota, New York, Wyoming, and Alaska. However, these states lost both the highly educated and the poorly educated, with Alaska hemorrhaging both types of people. Fourteen states (including Indiana) had a pattern similar to Indiana, where they lost the college-educated, but gained the poorly educated--Indiana had the highest rates of loss of college graduates, and the 3rd highest rate of increase in poorly educated migrants, after North Dakota and Wisconsin.