Mean center of the United States population

The mean center of the United States population is determined by the United States Census Bureau from the results of each national census. The Bureau defines it as follows:

Map showing changes to the mean center of population for the United States, 1790–2020 (US Census Bureau)[1]
Map of the Position of the U.S. Geographic Center of Area, Mean Center of Population, and Median Center of Population, 2020 (U.S. Census Bureau)[2]
The center of the US population, 13th census, near Bloomington, Indiana
The center of the US population, 13th census (1910), near Bloomington, Indiana

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. More specifically, this calculation is called the mean center of population.[3]

After moving roughly 600 mi (966 km) west by south during the 19th century, the shift in the mean center of population during the 20th century was less pronounced, moving 324 mi (521 km) west and 101 mi (163 km) south. Nearly 79% of the overall southerly movement happened between 1950 and 2000.

One occasional confusion is the misconception that the point splits the US population into two equal halves, such that half of Americans live east of the point, and the other half west of it, however, this is actually a property of the median center of US population, which is not weighted by geographic distance and lies in Gibson County, Indiana.

Location information since 1790 edit

US CensusCountyLocation description[3]Decimal coordinates[3]Distance from previous point[3]
1790Kent County, Maryland[a]23 miles east of Baltimore39°16′30″N 76°11′12″W / 39.27500°N 76.18667°W / 39.27500; -76.18667n/a
1800Howard County, Maryland18 miles west of Baltimore39°16′06″N 76°56′30″W / 39.26833°N 76.94167°W / 39.26833; -76.9416752 miles (84 km)
1810Loudoun County, Virginia40 miles west-northwest of Washington, D.C.39°11′30″N 77°37′12″W / 39.19167°N 77.62000°W / 39.19167; -77.6200047 miles (75 km)
1820Hardy County, West Virginia[b]16 miles east of Moorefield39°05′42″N 78°33′00″W / 39.09500°N 78.55000°W / 39.09500; -78.5500064 miles (103 km)
1830Grant County, West Virginia[b]19 miles west-southwest of Moorefield38°57′54″N 79°16′54″W / 38.96500°N 79.28167°W / 38.96500; -79.2816751 miles (81 km)
1840Upshur County, West Virginia[b]16 miles south of Clarksburg39°02′00″N 80°18′00″W / 39.03333°N 80.30000°W / 39.03333; -80.3000070 miles (113 km)
1850Wirt County, West Virginia[b]23 miles southeast of Parkersburg38°59′00″N 81°19′00″W / 38.98333°N 81.31667°W / 38.98333; -81.3166770 miles (113 km)
1860Pike County, Ohio20 miles southeast of Chillicothe39°00′24″N 82°48′48″W / 39.00667°N 82.81333°W / 39.00667; -82.81333103 miles (166 km)
1870Highland County, Ohio48 miles northeast of Cincinnati39°12′00″N 83°35′42″W / 39.20000°N 83.59500°W / 39.20000; -83.5950054 miles (87 km)
1880Boone County, Kentucky8 miles southwest of Cincinnati39°04′08″N 84°39′40″W / 39.06889°N 84.66111°W / 39.06889; -84.6611174 miles (119 km)
1890Decatur County, Indiana20 miles east of Columbus39°11′56″N 85°32′53″W / 39.19889°N 85.54806°W / 39.19889; -85.5480661 miles (99 km)
1900Bartholomew County, Indiana6 miles southeast of Columbus39°09′36″N 85°48′54″W / 39.16000°N 85.81500°W / 39.16000; -85.8150018 miles (30 km)
1910Monroe County, Indianain the city of Bloomington39°10′12″N 86°32′20″W / 39.17000°N 86.53889°W / 39.17000; -86.5388950 miles (80 km)
1920Owen County, Indiana8 miles south-southeast of Spencer39°10′21″N 86°43′15″W / 39.17250°N 86.72083°W / 39.17250; -86.7208313 miles (20 km)
1930Greene County, Indiana3 miles northeast of Linton39°03′45″N 87°08′06″W / 39.06250°N 87.13500°W / 39.06250; -87.1350029 miles (46 km)
1940Sullivan County, Indiana2 miles east-southeast of Carlisle38°56′54″N 87°22′35″W / 38.94833°N 87.37639°W / 38.94833; -87.3763917 miles (27 km)
1950Richland County, Illinois[c]
Clay County, Illinois[d]
8 miles north-northwest of Olney
3 miles northeast of Louisville
38°50′21″N 88°09′33″W / 38.83917°N 88.15917°W / 38.83917; -88.15917
38°48′15″N 88°22′08″W / 38.80417°N 88.36889°W / 38.80417; -88.36889
54 miles (87 km)
69 miles (110 km)
1960Clinton County, Illinois[e]6.5 miles northwest of Centralia38°35′58″N 89°12′35″W / 38.59944°N 89.20972°W / 38.59944; -89.2097258 miles (93 km)
1970St. Clair County, Illinois5 miles east-southeast of Mascoutah38°27′47″N 89°42′22″W / 38.46306°N 89.70611°W / 38.46306; -89.7061134 miles (55 km)
1980Jefferson County, Missouri0.3 mile west of DeSoto38°08′13″N 90°34′26″W / 38.13694°N 90.57389°W / 38.13694; -90.5738960 miles (96 km)
1990Crawford County, Missouri9.7 miles southeast of Steelville37°52′20″N 91°12′55″W / 37.87222°N 91.21528°W / 37.87222; -91.2152844 miles (71 km)
2000Phelps County, Missouri2.8 miles east of Edgar Springs37°41′49″N 91°48′34″W / 37.696987°N 91.809567°W / 37.696987; -91.809567[4]41 miles (66 km)
2010Texas County, Missouri2.7 miles northeast of Plato37°31′03″N 92°10′23″W / 37.517534°N 92.173096°W / 37.517534; -92.173096[5]25 miles (40 km)
2020Wright County, Missouri15 miles northeast of Hartville37°24′57″N 92°20′47″W / 37.415725°N 92.346525°W / 37.415725; -92.346525[2]12 miles (19 km)
  1. ^ In the first census (1790), the mean population center was about 7.4 miles northwest by west of Chestertown, Maryland.[4]
  2. ^ a b c d The mean population centers of 1820, 1830, 1840 and 1850 were in Virginia at the time of their censuses, before West Virginia's split from Virginia in 1863.[4]
  3. ^ Computation method used until 1950.
  4. ^ Current computation method.
  5. ^ The addition of Alaska and Hawaii to the union in 1959 contributed to moving the mean center of population about 2 miles (3.2 km) farther south and about 10 miles (16 km) farther west in the 1960 census.[3]

See also edit

References edit

  1. ^ "Mean Center of Population for the United States: 1790 to 2020" (PDF). Archived (PDF) from the original on November 16, 2021.
  2. ^ a b Bureau, US Census. "Position of the Geographic Center of Area, Mean and Median Centers of Population: 2020". Census.gov. Retrieved December 28, 2021.
  3. ^ a b c d e Centers of population computation, a U.S. Census Bureau publication, issued November 2021.
  4. ^ a b c 2000 U.S. Population Centered in Phelps County, Mo. Archived December 22, 2012, at the Wayback Machine, a U.S. Census Bureau press release.
  5. ^ Centers of Population for the 2010 Census, U.S. Census Bureau.