Top 10 Schools which had undergraduates win the MacArthur

Colleges and Universities A-Z University of Michigan
1

The foundation recently compiled and released a list of every school that has ever had an undergraduate receive the prestigious prize.

http://www.usnewsuniversitydirectory.com/articles/harvard-has-had-greatest-number-of-macarthur-fello_14946.aspx#.VWz-Ok9VhBc

Michigan is in the top 10, but I’m not clear on why this is undergraduate only. Michigan’s total count exceeds 20 graduates (across all schools/colleges).