[vwinsyee]

From an NYTimes article earlier this year [1]:

According to the report, [tenure and tenure-track] positions now make up only 24 percent of the academic work force, with the bulk of the teaching load shifted to adjuncts, part-timers, graduate students and full-time professors not on the tenure track.

The report was published by Center for the Future of Higher Education in 2012. Link: [2]

From the executive summary from this 2010 publication by the American Federation of Teachers [3]:

Altogether, part-time/adjunct faculty members account for 47 percent of all faculty, not including graduate employees. The percentage is even higher in community colleges, with part-time/adjunct faculty representing nearly 70 percent of the instructional workforce in those institutions.

[1] http://www.nytimes.com/2013/04/08/education/gap-in-universit... [2] http://www.insidehighered.com/sites/default/server_files/fil... [3] http://www.aft.org/pdfs/highered/aa_partimefaculty0310.pdf