Mean center of United States population

The mean center of U.S. population is determined by the United States Census Bureau from the results of each census. The Bureau defines it to be:

the point at which an imaginary, flat, weightless, and rigid map of the United States would balance perfectly if weights of identical value were placed on it so that each weight represented the location of one person on the date of the census.[2]

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

The following lists location information of the mean center of U.S. population since 1790:

US Census County Location description [3] decimal Coordinates [3]
1790 Kent County, Maryland 1.) 23 miles east of Baltimore.
1800 Howard County, Maryland 18 miles west of Baltimore.
1810 Loudoun County, Virginia 40 miles northwest by west of Washington, DC.
1820 Hardy County, Virginia (now W. Virginia) 2.) 16 miles east of Moorefield.
1830 Grant County, Virginia (now W. Virginia) 2.) 19 miles west-southwest of Moorefield.
1840 Upshur County, Virginia (now W. Virginia) 2.) 16 miles south of Clarksburg.
1850 Wirt County, Virginia (now W. Virginia) 2.) 23 miles southeast of Parkersburg.
1860 Pike County, Ohio 20 miles south by east of Chillcothe.
1870 Highland County, Ohio 48 miles east by north of Cincinnati.
1880 Boone County, Kentucky 8 miles west by south of Cincinnati, OH.
1890 Decatur County, Indiana 20 miles east of Columbus.
1900 Bartholomew County, Indiana 6 miles southeast of Columbus.
1910 Monroe County, Indiana in the city of Bloomington.
1920 Owen County, Indiana 8 miles south-southeast of Spencer.
1930 Greene County, Indiana 3 miles northeast of Linton.
1940 Sullivan County, Indiana 2 miles southeast by east of Carlisle.
1950 Richland County, Illinois 3.) 8 miles north-northwest of Olney. 3.) 3.)
1950 Clay County, Illinois 4.) 3 miles northeast of Louisville. 4.) 4.)
1960 Clinton County, Illinois 5.) 6-1/2 miles northwest of Centralia. 5.) 5.)
1970 St. Clair County, Illinois 5 miles east-southeast of Mascoutah.
1980 Jefferson County, Missouri 1/4 mile west of DeSoto.
1990 Crawford County, Missouri 9.7 miles southeast of Steelville.
2000 Phelps County, Missouri 2.8 miles east of Edgar Springs [4]
2010 Texas County, Missouri 2.7 miles northeast of Plato. [5]
2011 (estimated) Texas County, Missouri .5 miles southeast of Plato. [6]
2020 (projected) Wright County, Missouri 5.2 miles southeast of Grovespring. [6]

The 20.9 mile shift projected for the 2010-2020 period would be the slowest centroid movement since the Great Depression intercensus period of 1930-1940.

Notes on the table data

  1. In the first census (1790) the mean population center was near Chestertown, Maryland.[4]
  2. The mean population centers of 1820, 1830, 1840 and 1850 were in what is now West Virginia, given 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 moved the center about two miles (3 km) farther south and about ten miles (16 km) farther west in 1960.[3]

See also

References

  1. ^ Mean Center of Population for the United States: 1790 to 2010 from the U.S. Census Bureau website
  2. ^ Geographic population center from the U.S. Census Bureau website
  3. ^ a b c Centers of population computation, a U.S. Census Bureau publication, issued April 2001
  4. ^ a b c 2000 U.S. Population Centered in Phelps County, Mo., a U.S. Census Bureau press release
  5. ^ Centers of Population for the 2010 Census, U.S. Census Bureau
  6. ^ a b Alex Zakrewsky, Principal Planner/Data Manager, Middlesex County New Jersey Office of Planning