That's much more important than total seasons. If Bama and OSU, for instance, didn't have a lot of 3 star OL recruits, then this becomes less meaningful.
One analysis of the 2014 NFL draft indicated about 5.55 percent of eligible 3 stars were drafted (92 of 1,644). Presumably they looked just at the number of three stars of the college senior class as a baseline. In that same draft, 20 percent of four stars were drafted.
By comparison from 2000-2014, 55 percent of five stars were drafted.
Of that 58 in the OL denominator, Wisconsin had 12, so 1/12 was their OL hit rate, or 8.33%.
But over the last 5 NFL drafts, the Badgers have had 16 of 94 3-star recruits drafted (Jonathan Taylor from the 2017 recruiting class + 2011-2016 recruiting classes). 17%.
I always had it in my head that Iowa and Wisconsin were developing 3-star OL into studs. Not the case, apparently.
the breakdown of the 58:
Ohio State - 13
Iowa - 13
Wisconsin - 12
Michigan - 9
Alabama - 6
Notre Dame - 5