A Typology and Landscape of State Funding Formulas for Public Colleges and Universities from 2004 to 2021

State funding for public higher education institutions is crucial in supporting college access and completion, particularly among students from historically under-represented groups, yet little is known about the mechanisms that states use to allocate funds and how they are affected by financial challenges. This article provides the first detailed longitudinal typology of state funding strategies, focusing particularly on formula volatility and equity. We find a gradual shift toward funding models that include a combination of base-adjusted and enrollment and performance metrics, along with a growing focus on equity. During recessions, states frequently revert to across-the-board funding cuts, further disadvantaging under-resourced institutions.