Go to the http://www.census.gov/econ/concentration.html site.
Data for 2007, 2002 and 1997 are organized and classified by the North American Industry Classification System (NAICS). Use the data for 2007. Pick any industry, may be related to your major. Click on the “link to fact finder” (3rd column) in the row for the sector title of your choice.
Then select one of the tables. Click on it.
The 4th column’s heading is” Meaning of Firm concentration code” which has categories “all firms, 4 largest firms, 8 largest firms, 20 largest firms”, etc. The 8th column is the % date for the firms.
Is the industry you picked an oligopoly or not? Why?