This authorization will enable Fund staff to commission timely modeling of the impact of federal and state vaccination policies on the trajectory of the COVID-19 pandemic. In partnership with one or more university-based modeling groups with expertise in public health interventions, vaccine effectiveness, clinical epidemiology, and health policy, Fund staff will model several counterfactual scenarios, estimating trends in cases, hospitalizations, and deaths under each scenario. For example, for the period December 2020 to June 2021 we will examine four scenarios: actual, no vaccine, 1 million vaccines per day, and delayed. The models will use state-level data to construct two state-specific counterfactual scenarios: all states achieve daily vaccination rates equivalent to the average of the top five states as of June 30, 2021; and all states achieve daily vaccination rates equivalent to the average of the bottom five states as of June 30, 2021.