Concentration measures order the statistical units under observation according to their market share. However, there are situations where an order according to an exogenous variable is more appropriate or even
required. The present article introduces a generalized definition of market concentration and defines a corresponding concentration measure. It is shown that this generalized concept of market concentration satisfies the common axioms of (classical) concentration measures. In an application
example, the proposed approach is compared with classical concentration measures; the data are transfer spendings of German
Bundesliga soccer teams, the ``obvious'' exogenous order of the teams is the league ranking
