Mean center of the United States population
Map showing changes to the mean center of population for the United States, 1790–2010 (US Census Bureau)
[1]
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:
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 on one person. More specifically, this calculation is called the mean center of population.[2]
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.
Location info since 1790
US Census |
County |
Location description[2] |
Decimal coordinates[2] |
1790 |
Kent County, Maryland[lower-alpha 1] |
23 miles east of Baltimore |
39°16′30″N 76°11′12″W / 39.27500°N 76.18667°W / 39.27500; -76.18667 |
1800 |
Howard County, Maryland |
18 miles west of Baltimore |
39°16′06″N 76°56′30″W / 39.26833°N 76.94167°W / 39.26833; -76.94167 |
1810 |
Loudoun County, Virginia |
40 miles northwest by west of Washington, D.C. |
39°11′30″N 77°37′12″W / 39.19167°N 77.62000°W / 39.19167; -77.62000 |
1820 |
Hardy County, West Virginia[lower-alpha 2] |
16 miles east of Moorefield |
39°05′42″N 78°33′00″W / 39.09500°N 78.55000°W / 39.09500; -78.55000 |
1830 |
Grant County, West Virginia[lower-alpha 2] |
19 miles west-southwest of Moorefield |
38°57′54″N 79°16′54″W / 38.96500°N 79.28167°W / 38.96500; -79.28167 |
1840 |
Upshur County, West Virginia[lower-alpha 2] |
16 miles south of Clarksburg |
39°02′00″N 80°18′00″W / 39.03333°N 80.30000°W / 39.03333; -80.30000 |
1850 |
Wirt County, West Virginia[lower-alpha 2] |
23 miles southeast of Parkersburg |
38°59′00″N 81°19′00″W / 38.98333°N 81.31667°W / 38.98333; -81.31667 |
1860 |
Pike County, Ohio |
20 miles south by east of Chillicothe |
39°00′24″N 82°48′48″W / 39.00667°N 82.81333°W / 39.00667; -82.81333 |
1870 |
Highland County, Ohio |
48 miles east by north of Cincinnati |
39°12′00″N 83°35′42″W / 39.20000°N 83.59500°W / 39.20000; -83.59500 |
1880 |
Boone County, Kentucky |
8 miles west by south of Cincinnati |
39°04′08″N 84°39′40″W / 39.06889°N 84.66111°W / 39.06889; -84.66111 |
1890 |
Decatur County, Indiana |
20 miles east of Columbus |
39°11′56″N 85°32′53″W / 39.19889°N 85.54806°W / 39.19889; -85.54806 |
1900 |
Bartholomew County, Indiana |
6 miles southeast of Columbus |
39°09′36″N 85°48′54″W / 39.16000°N 85.81500°W / 39.16000; -85.81500 |
1910 |
Monroe County, Indiana |
in the city of Bloomington |
39°10′12″N 86°32′20″W / 39.17000°N 86.53889°W / 39.17000; -86.53889 |
1920 |
Owen County, Indiana |
8 miles south-southeast of Spencer |
39°10′21″N 86°43′15″W / 39.17250°N 86.72083°W / 39.17250; -86.72083 |
1930 |
Greene County, Indiana |
3 miles northeast of Linton |
39°03′45″N 87°08′06″W / 39.06250°N 87.13500°W / 39.06250; -87.13500 |
1940 |
Sullivan County, Indiana |
2 miles southeast by east of Carlisle |
38°56′54″N 87°22′35″W / 38.94833°N 87.37639°W / 38.94833; -87.37639 |
1950 |
Richland County, Illinois[lower-alpha 3] Clay County, Illinois[lower-alpha 4] |
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 |
1960 |
Clinton County, Illinois[lower-alpha 5] |
6.5 miles northwest of Centralia |
38°35′58″N 89°12′35″W / 38.59944°N 89.20972°W / 38.59944; -89.20972 |
1970 |
St. Clair County, Illinois |
5 miles east-southeast of Mascoutah |
38°27′47″N 89°42′22″W / 38.46306°N 89.70611°W / 38.46306; -89.70611 |
1980 |
Jefferson County, Missouri |
0.3 mile west of DeSoto |
38°08′13″N 90°34′26″W / 38.13694°N 90.57389°W / 38.13694; -90.57389 |
1990 |
Crawford County, Missouri |
9.7 miles southeast of Steelville |
37°52′20″N 91°12′55″W / 37.87222°N 91.21528°W / 37.87222; -91.21528 |
2000 |
Phelps County, Missouri |
2.8 miles east of Edgar Springs |
37°41′49″N 91°48′34″W / 37.696987°N 91.809567°W / 37.696987; -91.809567[3] |
2010 |
Texas County, Missouri |
2.7 miles northeast of Plato |
37°31′03″N 92°10′23″W / 37.517534°N 92.173096°W / 37.517534; -92.173096[4] |
2016 (estimated) |
Wright County, Missouri |
10 miles southwest of Plato |
37°25′29″N 92°22′41″W / 37.424816°N 92.377942°W / 37.424816; -92.377942[5] |
2020 (projected) |
Wright County, Missouri |
8.2 miles north of Hartville |
37°22′09″N 92°30′03″W / 37.369186°N 92.500850°W / 37.369186; -92.500850[5] |
- ↑ In the first census (1790), the mean population center was about 7.4 miles northwest by west of Chestertown, Maryland.[3]
- 1 2 3 4 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.[3]
- ↑ Computation method used until 1950.
- ↑ Current computation method.
- ↑ 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.[2]
The 20.7-mile (33.3 km) shift projected for the 2010–2020 period would be the shortest centroid movement since the Great Depression intercensal period of 1930–1940.[5]
See also
References