Unlike purchasing power data which shows where potential customers live, information on the retail sales and retail centrality show the attractiveness of a shopping location, in other words where potential customers shop. For retail companies, details on the viability of a location as a shopping location are essential. Retail centrality is calculated based on the ratio of the retail purchasing power of the population to the total retail sales. Thus, it provides information on the extent to which local retailers are able to also attract customers from surrounding areas.