At the Fifteenth New England Antitrust Conference in November 1981, the newly appointed Assistant Attorney General in charge of the Justice Department's Antitrust Division expressed dissatisfaction with his predecessors' method of measuring market concentration: We think that a rather more sophisticated way of thinking about concentration is appropriate. The four-firm concentration ratio has very serious drawbacks as a measure. It implicitly assumes that size distribution among the first four firms is irrelevant, which is obviously silly. It implicitly assumes that size distribution among firms five through N is irrelevant, which is obviously silly. There are better measures of concentration than that.'