Nearly three-quarters of American professors are contingent faculty. That’s a problem for students.

In 1975, 30 percent of college faculty were part-time. By 2011, 51 percent of college faculty were part-time, and another 19 percent were non–tenure track, full-time employees. In other words, 70 percent were contingent faculty, a broad classification that includes all non–tenure track faculty (NTTF), whether they work full-time or part-time.

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