A3. The brewery industry is often described as a duopoly. Explain how this description makes sense, even though there are more than two firms in the industry.

Market shares in the U.S. brewery (beer-manufacturing) industry are as follows. Brewery Anheuser-Busch Miller-Coors Constellation Heineken Pabst 2000 small companies Total Market Share (Percent) 40 23 11 4 2 each about 0.01 100