Abstract: A system and method of using transaction data for a population of account holders, such as credit card holders, is described. A frequency distribution input variable (Frd) and average amount distribution input variable (Avd) are calculated for each account and each merchant category. The Frd and Avd, either alone or in conjunction with each other, are used to assign accounts to clusters as well as calculate factors for factor analysis. The assigned cluster and calculated factors for each account are both used for further processing, such for as selecting accounts to which advertising materials will be sent or determining a surrogate account for a control group.