U.S. businesses are very dynamic. They have high rates of business openings and closings, as well as expansions and contractions. Business dynamics are a fundamental part of innovation, productivity growth, and job creation in our economy. Much of what we know empirically about business dynamics comes from research conducted over the last 25 years at the Center for Economic Studies (CES) and the Research Data Centers (e.g., the work of Dunne, Roberts, and Samuelson [1988] and Davis, Haltiwanger, and Schuh [1996]).