terms & definitions

• national terms & definitions
• housing unit terms & definitions

State & County

Births - total number of live births occurring to residents of an area during a time period, as estimated using reports from the Census Bureau’s Federal-State Cooperative Program for Population Estimates (FSCPE) and the National Center for Health Statistics. The birth rate expresses births during a time period as a percentage of an area’s population at the midpoint of the time period.

Deaths - total number of deaths occurring to residents of an area during a time period, as estimated using reports from the Census Bureau’s Federal-State Cooperative Program for Population Estimates (FSCPE) and the National Center for Health Statistics. The death rate expresses deaths during a time period as a percentage of an area’s population at the midpoint of the time period.

Estimated Components of Population Change - occurrences used by the Census Bureau to estimate changes in the population during a time period. These components consist of births, deaths, net internal migration and net international migration.

FIPS Code - Federal Information Processing Standards (FIPS) codes issued by the National Institute of Standards and Technology (NIST) that identify each area.

Natural Increase - births minus deaths. The rate of natural increase expresses natural increase during a time period as a percentage of an area’s population at the midpoint of the time period.

Net Internal Migration - the difference between internal in-migration to an area and internal out-migration from the same area during a time period. Internal in- and out-migration consist of moves where both the origin and the destination are with in the United States (excluding Puerto Rico). The net internal migration rate expresses net internal migration during a time period as a percentage of an area’s population at the midpoint of the time period.

Net International Migration - 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 people 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.

Net migration - net internal migration plus net international migration. The net migration rate expresses net migration during a time period as a percentage of an area’s population at the midpoint of the time period.

Numerical Population Change - the difference between the population of an area at the beginning and end of a time period.

Percent Population Change - the difference between the population of an area at the beginning and end of a time period, expressed as a percentage of the beginning population.

Population Estimate - the estimated population is the calculated number of people living in an area as of July 1. The estimated population is calculated from a components of change model that incorporates information on natural change (births, deaths) and net migration (net internal migration, net international migration) that has occurred in an area since a Census 2000 reference date.

Residual - The residual results from the application of a national population control to state and county population estimates. The residual is the difference in state and county population before and after the application of the control. The residual is not a demographic component of population change.