The effects of a budgetary formula change on 39 public colleges and universities in Virginia were assessed. As a state reaction to declining resources, the sample of 15 senior-level colleges and 24 community colleges had undergone a policy change for the 1978-1980 budget to make an adjustment upward in the student-faculty ratio. Attention was directed to three concerns: (1) the impact of the student-faculty ratio on instructional costs per student; (2) responses by the schools to the formula change, including instructional expenditures and the number of degree programs offered; and (3) institutional responses of senior-level colleges compared to community colleges. The conceptual framework for the analysis was derived from the "revenue theory of cost" (Bowen) and the "threshold level" of enrollment (Maynard). The primary data source was the Higher Education General Information Survey. As a result of institutional responses to revenue distress, per unit costs began to fall in both college sectors 2 years after the budgetary adjustment. Initially, per unit costs continued to rise as colleges were slow to adapt and were unwilling to retrench faculty. Instructional expenditure and number of degree programs per 100 full-time equivalent students were significant predictors of per unit instructional costs. (SW)