Assessing Alternative Modifications to the Affordable Care Act: Impact on Individual Market Premiums and Insurance Coverage.

The goals of the Affordable Care Act (ACA) are to enable all legal U.S. residents to have access to affordable health insurance and to prevent sicker individuals (such as those with preexisting conditions) from being priced out of the market. The ACA also instituted several policies to stabilize premiums and to encourage enrollment among healthy individuals of all ages. The law's tax credits and cost-sharing subsidies offer a "carrot" that may encourage enrollment among some young and healthy individuals who would otherwise remain uninsured, while the individual mandate acts as a "stick" by imposing penalties on individuals who choose not to enroll. In this article, the authors use the COMPARE microsimulation model, an analytic tool that uses economic theory and data to predict the effects of health policy reforms, to estimate how eliminating the ACA's individual mandate, eliminating the law's tax credits, and combined scenarios that change these and other provisions of the act might affect 2015 individual market premiums and overall insurance coverage. Underlying these estimates is a COMPARE-based analysis of how premiums and insurance coverage outcomes depend on young adults' propensity to enroll in insurance coverage. The authors find that eliminating the ACA's tax credits and eliminating the individual mandate both increase premiums and reduce enrollment on the individual market. They also find that these key features of the ACA help to protect against adverse selection and stabilize the market by encouraging healthy people to enroll and, in the case of the tax credit, shielding subsidized enrollees from premium increases. Further, they find that individual market premiums are only modestly sensitive to young adults' propensity to enroll in insurance coverage, and ensuring market stability does not require that young adults make up a particular share of enrollees.