In general, the study shows that available national data can be used to explore aggregate trends in revenues, costs, and prices for broad groups of institutions. Models using these data also can point out associations between revenue and expenditure variables and tuition—for example, as state appropriations for public 4-year institutions decrease, the average undergraduate tuition at this type of institution tends to increase. However, these statistical models are correlational in nature and cannot lead to definitive conclusions regarding the underlying relationships among changes in variables over time. Ideally, new models would need to be constructed to explore the simultaneous direct and indirect effects of costs, revenues, financial aid, market conditions and other external influences, family resources, and college prices.

Finally, even with future improvements in definitions and prospective data collection, the technique of cost analysis will always provide only partial answers to questions about the reasons for price increases at colleges and universities. Given the distinctive characteristics of higher education—such as the availability of nontuition sources of revenue—there is little reason to expect a consistent relationship between costs and prices across all institutions or groups of institutions, even though a specific relationship may be present at one particular institution. Nevertheless, the analyses presented in this report highlight trends and point to associations between variables that can lead to a better understanding of the nature of higher education finance.