Brown 据说据得少: http://www.insidehighered.com/news/2011/02/08/brown_faculty_oka This document claims that "In years past, Brown was identified by the American Association of University Professors as having the highest rate of tenured faculty -- at 82 percent -- among its peer Ivy League and highly selective private colleges, said Kertzer. The lowest among the data he cited was Columbia University, with 59 percent, while the University of Pennsylvania was closest to Brown, with 78 percent." average of 53% reported for the following universities (collectively): Florida, Illinois, Iowa, Maryland, Michigan, Northwestern, Penn State, Pittsburgh, Rutgers, and Wisconsin. from: http://www.psu.edu/president/pia/planning_research/reports/AIR_