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Methodology: Resident Population Estimates of the United States
Resident Population Universe Definition
Estimates of the United States resident population include persons resident in
the 50 States and the District of Columbia. They exclude residents of the
Commonwealth of Puerto Rico, and residents of the outlying areas under United
States sovereignty or jurisdiction (principally American Samoa, Guam, Virgin
Islands of the United States, and the Commonwealth of the Northern Mariana
Islands). The definition of residence conforms to the criterion used in Census
2000 which defines a resident of a specified area as a person "usually
resident" in that area. Estimates of resident population exclude the United
States Armed Forces overseas, as well as civilian United States citizens whose
usual place of residence is outside the United States.
Postcensal Estimation of Resident Population
Estimates of the United States population were derived quarterly by updating the
resident population enumerated in Census 2000 through the components of population
change. The following formula was applied to update each group:
- 2000 enumeration of resident population,
- + births to U.S. resident women,
- - deaths to U.S. residents,
- + net international migration,
- + net movement of U.S. Armed Forces.
- The 2000 enumerated resident population comes from the April 1,
2000 Decennial Census. For vintage 2003, the estimates base reflects
modifications processed through May 2003, to the Census 2000 population
as documented in the Count Question Resolution program.
- Registered births to United States resident women are estimated from data
supplied by the National Center for Health Statistics. The primary source
for this birth data can be found in the National Center for Health Statistics
(NCHS), Monthly Vital Statistics Report, Volume 51, Number 2, "Births:
Final Data for 2001," and similar publications of NCHS.
- Registered deaths to United States residents are also estimated from data
supplied by the National Center for Health Statistics. The primary source
for this death data can be found in the National Center for Health Statistics
National Vital Statistics Report, Volume 52, Number 3, "Deaths: Final
Data for 2001," and similar NCHS publications.
- International migration, in its simplest form, is defined as any movement across
U.S. (50 states and District of Columbia) borders. The U.S. Census Bureau makes
estimates of net international migration for the nation, states, and counties.
We estimate net international migration as: (1) net migration of the
foreign born, (2) net movement from Puerto Rico, (3) net movement
of the U.S. Armed Forces, and (4) emigration of the native born. The
largest component, net migration of the foreign born, includes lawful permanent
residents (immigrants), temporary migrants (such as students), humanitarian
migrants (such as refugees), and persons illegally present in the United
States. Currently, we do not estimate these components individually. The
Census definition of foreign born is available on the
foreign-born population page.
The national estimates of the international migration component incorporated
data available from the Census 2000 Supplementary Survey (C2SS), the 2001
Supplementary Survey (SSO1), and the 2002 Supplementary Survey (SS02) along
with estimates developed from the Demographic Analysis and Population
Estimates (DAPE) project (See Deardorff and Blumerman, 2001, "Evaluating
Components of International Migration: Estimates of the Foreign-Born Population
by Migrant Status in 2000", Population Division Working Paper Series No. 58).
An estimate of the net change in the combined components of legal immigration
to the United States, emigration of the foreign-born population from the
United States, temporary migrants, and the net residual foreign-born
population for the July 1, 2000 to July 1, 2002 period were developed
from special processing of the survey data. This processing involved the
development of a consistent set of population controls for July 1, 2000,
July 1, 2001 and July 1, 2002. The estimated annual net change in
the foreign-born population derived from the survey data (1.3 million) was
used for each period (April 1, 2000 to July 1, 2000 and each annual
period July 1, 2000 to July 1, 2003). The estimates from the DAPE
project provided the estimates of the emigration of the native population
(18,000 per year) and the net movement between the United States and Puerto
Rico (11,000 per year).
Independent estimates of each of the components of international migration are
not available.
- Armed Forces overseas strength statistics are supplied by the five branches
of the Armed Forces in the Departments of Defense (Army, Navy, Marines, and
Air Force) and Transportation (Coast Guard).
Notes
Population estimates are subject to revision, as revised input data become
available. These revisions normally occur once a year. |
