According to a new study by the American Association of University Professors, university and college faculty salaries have lagged far behind the substantial growth in university and college tuitions. Thus, adjusted for inflation, faculty salaries at four year doctoral private schools have gone up 7.7%. Tuitions at all private four year universities have gone up 28.9% over the last decade. The disparity at public schools is radically wider. Faculty salaries have gone up 0.7% at public doctoral schools while tuition at all publics has gone up 72% in that ten year period. And all of this has occurred as use of adjunct faculty continues to rise.
There are some unknowns. First, the data has some apple-to-apple comparison problems: the AAUP breaks out different types of universities (doctoral, masters, etc) for salary - but not tuition. We don't know how professional school faculty have fared compared to other professors. And we also don't know if universities are increasingly preferencing research over teaching - leading to lighter teaching loads and expanded faculty size. But some data is better than no data.
If nothing else, this report provides some good talking points.
Update: One other thing I didn't mention, but is worth noting, is that the tuition increases cited here are only hikes in sticker price. We have far less information on increases in real tuition. Many schools have raised their nominal tuition even as they enhanced merit or need based scholarships.
Click on the chart below to view details and a longer time horizon.