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Demographic Data

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What is Demographics?


Demography is the study of the static and dynamic aspects of a population (Becker, 2008).


Demographic Analysis—The study of components of variation and change in demographic variables and the relationships between them (Becker, 2008).

  • Static aspects of a population include characteristics at a point in time such as composition by (Becker, 2008):
    • Age
    • Economic characteristics
    • Marital status
    • Race
    • Sex
  • Dynamic aspects of a population include (Becker, 2008)
    • Fertility
    • Nuptiality
    • Growth
    • Migration
    • Mortality
  • Important aspect of demographics is "civil registration."
  • Civil registration is primarily administrative and allows us to (Becker, 2008):
    • Collect data on the vital events happening in a population (generally concerned with live births, deaths, marriages, and divorces).
    • Understand demographic characteristics of different populations at different points in time.
    • Civil registration generally covers (Becker, 2008):
      • Live birth
      • Marriage
      • Death

Census Data

What is a Census?

  • A census is a tool for compiling, analyzing, and disseminating demographic, economic, and social data pertaining to all persons in a country or in a well-delineated part of a country at a specified time (United Nations, 2000).
  • A census contains (Becker, 2008):
    • Demographic data (at least age and sex)
    • Economic data (e.g., occupation and income)
    • Social (e.g., education and housing)
  • Social characteristics of census data (Becker, 2008):
    • Ancestry
    • Language spoken at home
    • Migration (for example, residence in 1985)
    • Disability
    • Fertility
    • Veteran status
  • Economic characteristics of census data (Becker, 2008):
    • Labor force
    • Occupation, industry, and class of worker
    • Place of work and journey to work
    • Work experience in year of census
    • Income in year of census
    • Year last worked
  • Issues to look for in Census Data (Becker, 2008):
    • How the population is defined
    • How coverage of population changes between censuses
    • How are non-responses treated

About U.S. Census Data

  • The U.S. Census is mandated by Article I, Section 2 of the U.S. Constitution and takes place every 10 years. The data collected by the decennial census determine the number of seats each state has in the U.S. House of Representatives and is also used to distribute billions in federal funds to local communities.

Geographic Aspects of the U.S. Census

  • Census block: the smallest geographic unit used by the United States Census Bureau (Cromley & McLafferty, 2012b).
    • Each census block is bound by a set of connected street segments or other linear features, like rivers (Cromley & McLafferty, 2012b).
    • In cities, a census block may correspond to a city block, but in rural areas where there are fewer roads; blocks may be limited by other features (Cromley & McLafferty, 2012b).
  • Census Block Numbers: numbered uniquely with a four-digit census block number from 0000 to 9999 within census tracts (Cromley & McLafferty, 2012b).
  • Block Groups (BGs): statistical divisions of census tracts, are generally defined to contain between 600 and 3,000 people, and are used to present data and control block numbering (Cromley & McLafferty, 2012b).
  • Census tracts: small, relatively permanent statistical subdivisions of a county. A group of contiguous block/block groups, that have a population range of 1,200 - 8,000 people (Cromley & McLafferty, 2012b).

Major Census Data Sources

  • Data sources in this section are organized by topic, not by the survey instrument. However, it is important to know the major survey instruments employed by the U.S. Census Bureau.

Census Data Handouts

Census Bureau Training

The Census Bureau offers both web-based and in-person courses to help you access and use Census Bureau statistics. These free courses can teach you how to use our databases and mapping tools, find local and national demographic information for a variety of uses including grant proposals, economic data statistics for business plans, research papers, etc.

The US Census Bureau training page provides more information.

Vital Statistics

  • Local governments collect vital record data - data about births and deaths.


  • Birth records include the mother’s residential address, and geographical identifiers. This information has been used to study environmental and neighborhood influences on maternal and infant health (Cromley & McLafferty, 2012b).
  • Data about infant births is fairly accurate, but data for the mother can be spotty (Cromley & McLafferty, 2012b).
  • The United Nations recommends that the following be collected at a minimum for live birth registration (Becker, 2008):
    • Data on event
    • Date of occurrence
    • Date of registration
    • Place of occurrence
    • Type of birth/delivery
    • Attendance at birth
    • Data on infant:
      • Sex
        • Legitimacy status
        • Weight at birth
    • Data on Mother:
      • Age or date of birth
      • Number of previous children born alive
      • Date of marriage or duration of marriage
      • Place of usual residence


  • Mortality records: records generated from death certificates include information about the person and the cause of death (Cromley & McLafferty, 2012b).
    • Death certificates include the place where the person died, and the residence of the person that died.
    • Also, because of privacy concerns, data is only released in aggregated form (zip code or census tract).
  • The World Health Organization defines death as the permanent disappearance of all evidence of life at any time after live birth has taken place (post-natal cessation of vital functions without capability of resuscitation) (Becker, 2008).
    • It is important to note that this definition excludes fetal deaths.
    • Fetal Death is a death prior to the complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy (Becker, 2008).
  • WHO recommends three major categories of fetal deaths (Becker, 2008):
    • Early fetal death: < 20 completed weeks of gestation.
    • Intermediate fetal death: ≥ 20 but < 28 weeks.
    • Late fetal death: ≥ 28 weeks.
    • Stillbirth—Late fetal death, and should only be used if essential for national purposes.
  • The United Nations recommends that the following be collected at the minimum for death registration (Becker, 2008):
    • Date of occurrence
    • Date of registration
    • Place of occurrence
    • Cause of death
    • Certifier
  • Data on decedent (Becker, 2008):
    • Age or date of birth
    • Sex
    • Marital status
    • Occupation
    • Place of usual residence
    • Problems with Cause of Death Data (Becker, 2008; Cromley & McLafferty, 2012b)
      • Knowledge of certifier
      • Certifier may never see the deceased
      • Garbage codes”: missing, senility, etc.
      • Conflicting definitions of death: heart death versus loss of brain function.
      • Multiple and contributory causes of death
      • Medical classification changes over time
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