1. A computer implemented method of selecting customers comprising the steps of: selecting a reference market population; inputting demographic data on a multiplicity of households in a reference market population; selecting a customer population; inputting demographic data on a multiplicity of customers in a customer population; inputting a variable identifier to each of said multiplicity of customers in said customer population and to each of said multiplicity of households of said reference market population; sorting said demographic data on said multiplicity of households and said multiplicity of customers by a multiplicity of segments, each said segment representing one or more demographic characteristics; and calculating a statistical score representing each of said segments from a ratio comparing an amount of said multiplicity of said customers to an amount of said multiplicity of said households, and using said statistical score to select a group of households from said reference market population.