The visualizations for this 2018 data snapshot are retained primarily for historical purposes. The AAUP has since updated its methodology for calculating rates of tenure and contingency, especially with respect to graduate student employees and faculty members without formal faculty status. For more recent data and analysis, please consult the 2023 "Data Snapshot: Tenure and Contingency in US Higher Education" or the most recently published Annual Report on the Economic Status of the Profession.
The AAUP research department has taken a look at the data around tenure and the casualization of faculty labor. We looked at overall trends and broke out data regarding full-time contingent faculty and part-time and graduate-student instructors. Using data drawn from the Integrated Postsecondary Education Data System (IPEDS), our findings highlight the current status of the academic labor system in US higher education.
Our full data snapshot can be downloaded here