...seems unusually diverse in terms of institutional affiliation of those recognized. Here they are by school:
1. Harvard University (16)
2. Stanford University (11)
3. University of California, Los Angeles (8)
3. Yale University (8)
5. Massachussetts Institute of Technology (7)
5. Princeton University (7)
5. University of California, Berkeley (7)
5. University of Chicago (7)
9. Northwestern University (5)
9. University of Michigan, Ann Arbor (5)
11. Duke University (4)
11. University of Pennsylvania (4)
13. California Institute of Technology (3)
13. New York University (3)
13. University of California, Davis (3)
13. University of Illinois, Urbana-Champaign (3)
13. University of Virginia (3)
Two each: Syracuse University; UC Santa Barbara; UC San Diego; Columbia University; UC San Francisco; Indiana University, Bloomington; Cornell University; Stony Brook University; University of Washington, Seattle; University of Oregon.
One each: University of Southern California; University of Minnesota; Brown University; Louisiana State University; Rice University; Boston University; Georgia Institute of Technology; University of Maryland; University of Rhode Island; Johns Hopkins; UC Irvine; University of Connecticut; University of Georgia; Kent State University; Clark University; Georgetown; Colorado State University; UT Austin; University of Wisconsin, Madison; University of Colorado, Boulder; Baylor College of Medicine; Emory University.
Last year's breakdown here.