Each decade, after it tabulates the decennial census, the Census Bureau calculates the center of population. The center is determined as the place where an imaginary, flat, weightless and rigid map of the United States would balance perfectly if all residents were of identical weight.

You can watch the Center of Population move across the country and learn more about what historical factors contributed to this movement, on the Census Bureau’s interactive map . The map is easy to share by embedding it on your own website.

On Wednesday, Census Bureau geographer Theodore Sickley will discuss how the center of population is determined and what we can learn about the population growth and distribution of our country through the center’s travels westward since the 1790 Census. Join us at 11 AM EDT for this live Ustream video event . Theodore will answer questions posed from the public on Facebook and Twitter during the live broadcast.

Historically, the center of population has followed a trail that reflects the sweep of the nation’s brush stroke across America’s population canvas. The sweep reflects the settling of the frontier, waves of immigration and the migration west and south. Since 1790, the location has moved in a westerly, then a more southerly pattern. In 2000, the new center of population in Edgar Springs, Mo., was more than 1,000 miles from the first center in 1790, which was near Chestertown, Md.

In 2010, the center moved in a more southerly direction than in previous decades, to near Plato, Mo., an incorporated village in Texas County. The distance moved—23.4 miles—is the shortest distance since 1970. This southerly drift and shorter distance can be attributed to a strong pull on the center by population growth in the Southeast—Georgia, Florida, and the Carolinas—as well as growth in Texas.

Learn the mean center of population for your state.

View the interactive map.

View the live Ustream event on Wednesday, May 11 at 11 AM EDT.