In the study of supply-chain management, the concept of centroids has become a useful economic consideration. In mathematics and physics, a centroid is the arithmetic mean position of all the points in a plane figure. For supply chain management, a centroid is a location with a high proportion of a country's population and a high proportion of its manufacturing, generally within . In the US, two major supply chain centroids have been defined, one near Dayton, Ohio, and a second near Riverside, California.