Despite their strong positive average returns across numerous asset classes, momentum strategies can experience infrequent and persistent strings of negative returns. These momentum crashes are partly forecastable. They occur in "panic" states - following market declines and when market...

This paper examines the economic environments in which past U.S. stock market booms occurred as a first step toward understanding how asset price booms come about and whether monetary policy should be used to defuse booms. We identify several episodes of sustained rapid rise in equity prices in...