Juergen Jung and Chung Tran
We study the optimal progressivity of a personal income tax system in an environment where individuals are exposed to idiosyncratic shocks to health and labor productivity over the lifecycle. Our results, based on a dynamic general equilibrium model calibrated to the US economy, indicate that accounting for health risk substantially aects the social insur- ance/redistribution role of a progressive income tax system. When health risk is present but access to health insurance is limited, the optimal income tax system is more progressive in order to provide more social insurance/redistribution to unhealthy low income individuals. However, when more inclusive health insurance systems are considered, such as Medicare for all, then the optimal level of tax progressivity decreases signicantly. Importantly, when health expenditure risk is eliminated, the optimal income tax progressivity becomes more similar to the optimal progressivity level in previous studies using models with income risk only.