This map displays the relative numbers of outbound college students from each state, defined as a student who is a resident of that given state but is attending college in a different state.
This map displays the relative numbers of inbound college students entering each state, defined as a student who is a resident of a different state but is attending college in that given state.
This map displays the relative numbers of students remaining within their residential state for college.
Note: The average percentage of students remaining in-state for college in the US is exceptionally high and thus states with lower percentages are displayed as closer to black than they are to blue in this representation since the data is so skewed toward the higher end of the spectrum for this particular scenario.
This information was compiled from the College Board's 2015 data set. A PDF version of the data used is available here, or you can download the Excel sheet I used. More detailed information about the data and the process I used to create this visualization is available on GitHub.