Bloomberg ranks Howard MBA as #1 for Diversity despite only admitting black students, two years in a row. Thoughts?

Bloomberg released their MBA rankings today and if you filter by Diversity score, Howard was ranked as #1. Under the Howard MBA breakdown, you can see that 100% of their students are black. This happened last year as well, so it definitely isn't a fluke. Does this not inherently contradict the meaning of the word Diversity? Every other school has a mix of races (except Utah and Case Western but I assume their data got messed up), so this logically means that Howard is the least diverse MBA of all schools included in the ranking.

Also, clearly Howard must be breaking some sort of rule/law right? I find it very hard to believe that there was not a single non-black student who applied, got accepted, and enrolled at Howard in this two year period (it was 100% black last year as well). I understand that it is historically black but surely that doesn't give them the right to deny any non-blacks. This seems pretty messed up and would be all over the news if it was the other way around.