Book excerpt: Brookings Papers on Economic Activity (BPEA) provides academic and business economists, government officials, and members of the financial and business communities with timely research on current economic issues. Contents: All Medicaid Expansions Are Not Created Equal: The Geography and Targeting of the Affordable Care Act Craig Garthwaite, John Graves, Tal Gross, Zeynal Karaca, Victoria Marone, and Matthew J. Notowidigdo Policies and Payoffs to Addressing America’s College Graduation Deficit Christopher Avery, Jessica Howell, Matea Pender, and Bruce Sacerdote The Optimal Inflation Target and the Natural Rate of Interest Philippe Andrade, Jordi Galí, Hervé Le Bihan, and Julien Matheron Inflation Dynamics: Dead, Dormant, or Determined Abroad? Kristen J. Forbes Macri’s Macro: The Elusive Road to Stability and Growth Federico Sturzenegger Progressive Wealth Taxation Emmanuel Saez and Gabriel Zucman