Yellen is Vice Chair of the board of governors as a woman. Also, Esther George is on the BoG. Roger Ferguson (Black American) was Vice Chair for a time and was being considered for the chairmanship.
Not that I actually give a flying hoot about diversity for the sake of diversity. Let the best (wo)man get the job — race or gender should not be considerations either way.
Keep in mind that groups that were traditionally under-represented need to rise through the ranks. I’m NOT for promoting someone just to have a token individual of a given race or gender at the top. Equality and balance will come in time, but it has to be a natural process.
