What's the Difference between the Census Data?

Source: U.S. Census Bureau

Apportionment

The fundamental reason for conducting the decennial census of the United States is to apportion the members of the House of Representatives among the 50 states. A state's resident population consists of those persons "usually resident" in that state (where they live and sleep most of the time). A state's apportionment population is the sum of its resident population and a count of overseas U.S. military and federal civilian employees (and their dependents living with them) allocated to the state, as reported by the employing federal agencies. Based on the Census 2000 apportionment, each member of the U.S. House of Representatives represents an average population of 646,952.

 

Redistricting - P.L. 94-171

This product contains summary population counts for two universes, total population and population 18 years and over. The data were derived from the basic questions asked on all census questionnaires. These are often called the 100-percent questions.
This file contains four tables:

• a count of all persons by race.
• a count of the population 18 years and over by race.
• a count of Hispanic or Latino and a count of not Hispanic or Latino by race for all persons.
• a count of Hispanic or Latino and a count of not Hispanic or Latino by race for the population 18 years and over.

 

1990 Redistricting - P.L. 94-171

The files contain a count of all persons and all housing units in the geographic area. They also provide a race count (five race categories) and a count of all persons of Hispanic origin and persons 18 years old and over of Hispanic origin. In addition, data are provided for all persons not of Hispanic origin and persons 18 years old and over not of Hispanic origin by race (five race categories).

 

Census Demographic Profile 1 (DP 1)

The Profiles of General Demographic Characteristics contain the 100-percent data, which is the information compiled from the questions asked of all people and about every housing unit. The Profiles of General Demographic Characteristics population items include sex, age, race, Hispanic or Latino, household relationship, household type, group quarters population, housing occupancy, and housing tenure. The profiles include a total of 71 population and 25 housing data items.

 

Census Demographic Profile 2-4 (DP 2-4)

The Profiles of Social, Economic, and Housing Demographic Characteristics contain sample data. The sample data were asked of a sample of housing units and persons in group quarters (e.g., college dormitories). The sample items include sample population topics, such as school enrollment, educational attainment, marital status, grandparents as caregivers, veteran status, disability status of the civilian noninstitutionalized population, residence, nativity and place of birth, region of birth of the foreign born, language spoken at home, ancestry, employment status, commuting to work, occupation, industry, class of worker, income, and poverty status. The sample items also include sample housing topics, such as units in structure, year structure built, rooms, year householder moved into unit, vehicles available, house heating fuel, occupants per room, value, mortgage status and selected monthly owner costs, selected monthly owner costs as a percentage of household income, gross rent, and gross rent as a percentage of household income.

 

Summary File 1 (SF 1)

Summary File 1 (SF 1) includes population and housing characteristics for the total population, population totals or an extensive list of race (American Indian and Alaska Native tribes, Asian, and Native Hawaiian and Other Pacific Islander) and Hispanic or Latino groups, and population and housing characteristics or a limited list of race and Hispanic or Latino groups. Population and housing items may be cross tabulated. Selected aggregates and medians also are provided. SF 1 contains the 100-percent data, which is the information compiled from the questions asked of all people and about every housing unit. Population items include sex, age, race, Hispanic or Latino, household relationship, and group quarters. Housing items include occupancy status, vacancy status, and tenure (owner occupied or renter occupied). There is a total of 171 population tables (identified with a "P") and 56 housing tables (identified with an "H") shown down to the block level, and 59 population tables shown down to the census tract level (identified with a "PCT") for a total of 286 tables. There are 14 population tables and 4 housing tables shown down to the block level, and 4 population tables shown down to the census tract level that are repeated by major race and Hispanic or Latino groups.

 

Summary File 2 (SF 2)

Summary File 2 (SF 2) contains the 100-percent data (the information compiled from the questions asked of all people and about every housing unit). Population items include sex, age, race, Hispanic or Latino, household relationship, and group quarters. Housing items include occupancy status, vacancy status, and tenure (owner occupied or renter occupied). SF 2 includes population characteristics, such as sex by age, average household size, household type, relationship by household type (including living alone), unmarried-partner households, nonrelatives by household type, and own children under 18 years by family type and age. The file includes housing characteristics, such as tenure, tenure by age of householder, and tenure by household size for occupied housing units. Selected aggregates and medians also are provided. These 100-percent data are presented in 36 population tables (matrices) and 11 housing tables, identified with "PCT" and "HCT", respectively. Each table is iterated for 250 population groups: the total population, 132 race groups, 78 American Indian and Alaska Native tribe categories (reflecting 39 individual tribes), and 39 Hispanic or Latino groups. The presentation of SF 2 tables for any of the 250 population groups is subject to a population threshold of 100 or more people. That is, if there are fewer than 100 people in a specific population group in a specific geographic area, their population and housing characteristics data are not available for that geographic area in SF 2.

 

Summary File 3 (SF 3)

Summary File 3 (SF 3) contains the sample data, which is the information compiled from the questions asked of a sample of all people and housing units. Population items include basic population totals; urban and rural; households and families; marital status; grandparents as caregivers; language and ability to speak English; ancestry; place of birth, citizenship status, and year of entry; migration; place of work; journey to work (commuting); school enrollment and educational attainment; veteran status; disability; employment status; industry, occupation, and class of worker; income; and poverty status. Housing items include basic housing totals; urban and rural; number of rooms; number of bedrooms; year moved into unit; household size and occupants per room; units in structure; year structure built; heating fuel; telephone service; plumbing and kitchen facilities; vehicles available; value of home; monthly rent; and shelter costs.

In Summary File 3, population tables are identified with a "P" and housing tables are identified with an "H" prefix, followed by a sequential number. The "P" and "H" tables are shown for the block group and higher levels of geography, while the "PCT" and "HCT" tables are shown for the census tract and higher levels of geography. There are 16 "P" tables, 15 "PCT" tables, and 20 "HCT" tables that bear an alphabetic suffix on the table number, indicating that they are repeated for nine major race and Hispanic or Latino groups. Summary File 3 contains a total of 813 unique tables -- 484 population tables and 329 housing tables compiled from a sample of approximately 19 million housing units (about 1 in 6 households) that received the Census 2000 long-form questionnaire. Fifty-one tables are repeated for nine major race and Hispanic or Latino groups: White alone; Black or African American alone; American Indian and Alaska Native alone; Asian alone; Native Hawaiian and Other Pacific Islander alone; Some other race alone; Two or more races; Hispanic or Latino; and White alone, not Hispanic or Latino.

Summary File 3 presents data in a hierarchical sequence down to the block group for many tabulations, but only to the census tract levels for others. Summ aries are included for other geographic areas such as Zip Code Tabulation Areas (ZCTAs^™) and Congressional districts (106^th Congress).

Summary File 4 (SF 4)

Summary File 4 (SF 4) contains the sample data, which is the information compiled from the questions asked of a sample of all people and housing units. Population items include basic population totals; urban and rural; households and families; marital status; grandparents as caregivers; language and ability to speak English; ancestry; place of birth, citizenship status, and year of entry; migration; place of work; journey to work (commuting); school enrollment and educational attainment; veteran status; disability; employment status; industry, occupation, and class of worker; income; and poverty status. Housing items include basic housing totals; urban and rural; number of rooms; number of bedrooms; year moved into unit; household size and occupants per room; units in structure; year structure built; heating fuel; telephone service; plumbing and kitchen facilities; vehicles available; value of home; monthly rent; and shelter costs.

In Summary File 4, the sample data are presented in 213 population tables (matrices) and 110 housing tables, identified with "PCT" and "HCT"’ respectively. Each table is iterated for 336 population groups: the total population, 132 race groups, 78 American Indian and Alaska Native tribe categories (reflecting 39 individual tribes), 39 Hispanic or Latino groups, and 86 ancestry groups. The presentation of SF 4 tables for any of the 336 population groups is subject to a population threshold. That is, if there are fewer than 100 people (100 percent count) in a specific population group in a specific geographic area, and there are fewer than 50 unweighted cases, their population and housing characteristics data are not available for that geographic area in SF 4. For the ancestry iterations, only the 50 unweighted cases test can be performed. Population and housing items may be cross tabulated. Selected aggregates and medians also are provided.

Public Use Microdata Sample (PUMS)

Microdata are the individual records which contain information collected about each person and housing unit. They include the census basic record types, computerized versions of the questionnaires collected from households, as coded and edited during census processing. The Census Bureau uses these confidential microdata in order to produce the summary data that go into the various reports, summary files, and special tabulations. Public use microdata samples are extracts from the confidential microdata taken in a manner that avoids disclosure of information about households or individuals. For Census 2000, the microdata are only available to the public through the Public Use Microdata Sample (PUMS) products.

Public Use Microdata Sample (PUMS) files contain records representing 5-percent or 1-percent samples of the occupied and vacant housing units in the U.S. and the people in the occupied units. Group quarters people also are included. The file contains individual weights for each person and housing unit, which when applied to the individual records, expand the sample to the relevant total.

Some of the items included on the housing record are: acreage; agricultural sales; allocation flags for housing items; bedrooms; condominium fee; contract rent; cost of utilities; family income in 1999; family, subfamily, and relationship recodes; farm residence; fire, hazard, and flood insurance; fuels used; gross rent; heating fuel; household income in 1999; household type; housing unit weight; kitchen facilities; linguistic isolation; meals included in rent; mobile home costs; mortgage payment; mortgage status; plumbing facilities; presence and age of own children; presence of subfamilies in household; real estate taxes; rooms; selected monthly owner costs; size of building (units in structure); state code; telephone service; tenure; vacancy status; value (of housing unit); vehicles available; year householder moved into unit; and year structure built.

Some of the items included on the person record are: ability to speak English; age; allocation flags for population items; ancestry; citizenship; class of worker; disability status; earnings in 1999; educational attainment; grandparents as caregivers; Hispanic origin; hours worked; income in 1999 by type; industry; language spoken at home; marital status; means of transportation to work; migration Public Use Microdata Area (PUMA); migration state; mobility status; veteran period of service; years of military service; occupation; person's weight; personal care limitation; place of birth; place of work PUMA; place of work state; poverty status in 1999; race; relationship; school enrollment and type of school; time of departure for work; travel time to work; vehicle occupancy; weeks worked in 1999; work limitation status; work status in 1999; and year of entry.

Census 2000 Supplementary Survey (C2SS)

The Census 2000 Supplementary Survey was a Decennial Census program designed to demonstrate the feasibility of collecting long form type information at the same time as, but separate from, the Decennial Census. It used the questionnaire and methods developed for the American Community Survey to collect demographic, social, economic, and housing data from a national sample of 700,000 households in 1,203 counties. Group quarters were not included in the sample.

The Census 2000 Supplementary Survey was designed to be used in combination with data from the American Community Survey comparison site tests to produce annual estimates. Economic, demographic, and housing characteristics from the Supplementary Surveys are reported for the United States as a whole, the 50 states, and the District of Columbia, as well as large counties and cities. The Census 2000 Supplementary Survey data provided an early look at the detailed characteristics of the U.S. population in 2000. However, as the official census sample data become available, they should be used instead of the Census 2000 Supplementary Survey to describe the population in 2000 and to look at changes from 1990 to 2000.

The Census 2000 Supplementary Survey (C2SS) tables are estimates of demographic and economic characteristics of people, households and housing units (occupied and vacant) for areas with a population of 250,000 or more.