The concept of the center of population as used by the U.S. Census Bureau is that of a balance point. The center of population is the point at which an imaginary, weightless, rigid, and flat (no elevation effects) surface representation of the 50 states (or 48 conterminous states for calculations made prior to 1960) and the District of Columbia would balance if weights of identical size were placed on it so that each weight represented the location of one person.
Reference Maps
<h6>Centers of Population Computation Methodology</h6> Methodology used by the U.S. Census Bureau for the computation of the centers of population from 1950 to 2000.
<h6>Press Release</h6> 2000 U.S. Population Centered in Phelps County, Missouri.