Population

The Virginia Health Statistics Program uses the Centers for Disease Control and Prevention (CDC) Bridged-Race Postcensal population estimates.  According to the CDC, “Postcensal population estimates are estimates made for the years following a census, before the next census has been taken. Postcensal estimates are derived by updating the resident population enumerated in the decennial census using various measures of population change”.[1] For more information on population projection methodology please visit the CDC website.  For detailed Information on specific Virginia population projections please see the Virginia Geographic and Population Information Visualization .  Furthermore, Virginia follows the National Center for Health Statistics (NCHS) guidelines when classifying Race and Ethnicity.  For more information on Bridged-Race and Ethnicity please visit the NCHS website.

Virginia Health Statistics Program applies the United States Census Bureau's Population Estimates Program (PEP) for population estimates at The Federal Information Processing Standard (FIPS) code level, which is equivalent to the city/county level for the Commonwealth of Virginia.  These population estimates are used by the Virginia Department of Health for a multitude of calculations and analysis to include time series population growth and with vital event rate formulas.  Further information, technical information, and methodology for population estimates can be found at The United States Census Bureau's website.

The Virginia Locality profile has been developed  by employing the American Community Survey (ACS).  The ACS is a survey that is conducted at the Federal level by the United States Census Bureau which aims to provide continual measurements to produce annual estimates for small localities[2].  For more information, data and methodology please visit the United States Census Bureau website American Community Survey.

For the Life Expectancy and Life Tables, The Virginia Department of Health follows the Chiang Method which defines the measure as: "The average number of years a baby born in a particular area or population can be expected to live if it experiences the current age-specific mortality rates of that particular area or population throughout its life".[1]  For more information on the methodology of the Chiang Life Table and Life Expectancy Method please visit the World Health Organization Institutional Repository for Information Sharing.  Additionally, the Virginia Health Statistics Program has developed Life Expectancy by Census Tract Visual map and table.   This was completed by using both the Sub-County Assessment of Life Expectancy (SCALE)[3] Project guidelines and the South East Public Health Observatory (SEPHO) Life Expectancy Calculator.