There has been much conversation about this in academia lately but here are some actual numbers about the percentages of tenured and non-tenured faculty:

Once, being a college professor was a career. Today, it’s a gig.

That, broadly speaking, is the transformation captured in the graph below from a new report by the American Association of University Professors. Since 1975, tenure and tenure-track professors have gone from roughly 45 percent of all teaching staff to less than a quarter. Meanwhile, part-time faculty are now more than 40 percent of college instructors, as shown by the line soaring towards the top of the graph.

This doesn’t actually mean that there are fewer full-time professors today than four-decades ago. College faculties have grown considerably over the years, and as the AAUP notes, the ranks of the tenured and tenure-track professoriate are up 26 percent since 1975. Part-time appointments, however, have exploded by 300 percent. The proportions vary depending on the kind of school you’re talking about. At public four-year colleges, about 64 percent of teaching staff were full-time as of 2009. At private four-year schools, about 49 percent were, and at community colleges, only about 30 percent were. But the big story across academia is broadly the same: if it were a move, it’d be called “Rise of the Adjuncts.”

This is quite a shift over several decades. While there is a lot to explore here about economic life in colleges and universities, there is another question we could ask about how this affects the college experience: how does this change educational experiences and outcomes? Are students learning more or less depending on what kind of faculty in the classroom? Does it matter?