Every 10 years since the first census in 1790, the Census Bureau has also calculated what it calls the country’s “center of population.” This is the point at which, says the Bureau, “an imaginary, flat, weightless and rigid map of the United States would balance perfectly if everyone were of identical weight” – in other words “the average location of where people in the United States live.” And that place is Hartville, Missouri – or, more accurately, a point 15 miles from the town.

“The center of population is officially marked,” adds the Bureau, “with a survey monument by the National Oceanic and Atmospheric Administration’s (NOAA) National Geodetic Survey (NGS), the U.S. government’s authoritative source for precise latitude, longitude and elevation measurements.”

When the results of the first Census, in 1790, were revealed, the center of population was in Kent County, Maryland, near Baltimore. Since then, it has moved steadily west, as the nation grew and people migrated. As of 1980, the location has been somewhere in Missouri. (These are the states where the population has grown the most since 1880.)

According to the Census Reporter, Hartville has a population of 547. It covers .7 square miles. Almost the entire population of the town, some 96%, is white. The town is extremely poor, with a poverty rate of 30.5%, compared to a U.S. average of about 11%. Median household income is $22,000, while the national figure is over $68,000. (See what income level is considered middle class in your state.)

Rob Tucker, the mayor of Hartville, was pleased to learn that his town had been named, as he put it, “the heart of America.” A commemorative monument will be unveiled in Hartville this spring.

The Census Bureau also calculates the population center of each state, according to the same principles. Because of the way the point is determined, the population center of Missouri isn’t Hartville, but Saint Thomas, some 80 miles to the northeast.

Click here to see the population center of every state