Introducing a new way to navigate by topics. Access the latest news, data, publications and more around topics of interest.
Our population statistics cover age, sex, race, Hispanic origin, migration, ancestry, language use, veterans, as well as population estimates and projections.
This section provides information on a range of educational topics, from educational attainment and school enrollment to school districts, costs and financing.
We measure the state of the nations workforce, including employment and unemployment levels, weeks and hours worked, occupations, and commuting.
Our statistics highlight trends in household and family composition, describe characteristics of the residents of housing units, and show how they are related.
Health statistics on insurance coverage, disability, fertility and other health issues are increasingly important in measuring the nation's overall well-being.
We measure the housing and construction industry, track homeownership rates, and produce statistics on the physical and financial characteristics of our homes.
The U.S. Census Bureau is the official source for U.S. export and import statistics and regulations governing the reporting of exports from the U.S.
The U.S. Census Bureau provides data for the Federal, state and local governments as well as voting, redistricting, apportionment and congressional affairs.
Search an alphabetical index of keywords and phrases to access Census Bureau statistics, publications, products, services, data, and data tools.
Geography provides the framework for Census Bureau survey design, sample selection, data collection, tabulation, and dissemination.
Geography is central to the work of the Bureau, providing the framework for survey design, sample selection, data collection, tabulation, and dissemination.
Find resources on how to use geographic data and products with statistical data, educational blog postings, and presentations.
The Geographic Support System Initiative will integrate improved address coverage, spatial feature updates, and enhanced quality assessment and measurement.
Work with interactive mapping tools from across the Census Bureau.
Find geographic data and products such as Shapefiles, KMLs, TIGERweb, boundary files, geographic relationship files, and reference and thematic maps.
Metropolitan and micropolitan areas are geographic entities used by Federal statistical agencies in collecting, tabulating, and publishing Federal statistics.
Find information about specific partnership programs and learn more about our partnerships with other organizations.
Definitions of geographic terms, why geographic areas are defined, and how the Census Bureau defines geographic areas.
We conduct research on geographic topics such as how to define geographic areas and how geography changes over time.
Visit our library of Census Bureau multimedia files. Collection formats include audio, video, mobile apps, images, and publications.
Official audio files from the Census Bureau, including "Profile America," a daily series of bite-sized statistics, placing current data in a historical context.
Infographics include information on the Census Bureau's history of data collection, our nation's veterans and the American Community Survey.
Stock photos that illustrate official Census Bureau operations and activities.
Read briefs and reports from Census Bureau experts.
Watch Census Bureau vignettes, testimonials, and video files.
Read research analyses from Census Bureau experts.
Access data through products and tools including data visualizations, mobile apps, interactive web apps and other software.
Developer portal to access services and documentation for the Census Bureau's APIs.
Explore Census Bureau data on your mobile device with interactive tools.
Find a multitude of DVDs, CDs and publications in print by topic.
These external sites provide more data.
Download extraction tools to help you get the in-depth data you need.
Learn more about our data from this collection of e-tutorials, presentations, webinars and other training materials. Sign up for training sessions.
Explore Census data with interactive visualizations covering a broad range of topics.
Learn how we serve the public as the most reliable source of data about the nation's people and economy.
Information about the U.S. Census Bureau.
Information about what we do at the U.S. Census Bureau.
Our researchers explore innovative ways to conduct surveys, increase respondent participation, reduce costs, and improve accuracy.
Our surveys provide periodic and comprehensive statistics about the nation, critical for government programs, policies, and decisionmaking.
Learn about other opportunities to collaborate with us.
Explore the rich historical background of an organization with roots almost as old as the nation.
Explore prospective positions available at the U.S. Census Bureau.
Information about the current field vacancies available at the U.S. Census Bureau Regional Offices.
Discover the latest in Census Bureau data releases, reports, and events.
The Census Bureau's Director writes on how we measure America's people, places and economy.
Find interesting and quirky statistics regarding national celebrations and major events.
Profile America is a daily, 60-second feature that uses interesting vignettes for that day to highlight information collected by the Census Bureau.
Find media toolkits, advisories, and all the latest Census news.
See what's coming up in releases and reports.
ASCII data set information
Deciding which data files to use
Using Microsoft Access ™
Using SAS ™
Using other database programs
Data file directory
File documentation [, 5.32 MB]
Census 2000 Data Products support
A data set consists of a geographic identifier (Geo ID) file and thirty eight data files. The Geo ID file should initially appear last in the data directory and will contain "geo" as part of its' filename. The Geo ID file is not a "header file" as it is linked horizontally with the data files, not placed on top of them vertically. Any data file used must be linked to the Geo ID file (on the unique key field LOGRECNO 1) because the data files do not contain any geographic identifiers. Each data file contains a different set of demographic data tables.
None of the files contain a header record (first record or row with field names). Microsoft Access ™ and SAS ™ templates and instructions are provided to assist in importing the ASCII text files into these programs. The Geo ID file is fixed width with no field delimiters while all thirty eight data files are variable length with comma field delimiters.
The field SUMLEV 2 in the Geo ID file identifies the summary level (area type) of each record. A combination of the geographic identifier codes for each element in the complete summary level description is used to identify the specific area being tabulated. 100% housing unit and population counts are also contained in the Geo ID file.
The same set of tables is repeated (iterated) for each of 336 different population groups in separate data sets. The same geographic file is used in each data set. The field CHARITER contains the code of the population group being tabulated. A complete code list for this field appears in Appendix H of the file documentation. The value of CHARITER in the geographic file is always "001". Always use the value of CHARITER in the linked data file when doing a query.
There is a one to one correspondence based on LOGRECNO between the Geo ID file and each data file for the "All Persons" iteration. This is not necessarily the case for other iterations as areas where a population threshold is not met are not included in the data files for that iteration.
2 Chapter 4 (Summary Level Sequence Chart) of the file documentation contains a code list for SUMLEV (summary level) and a list of available geographic component codes for each summary level or area type (see the Footnote Section of Chapter 7 (Data Dictionary) for a code list for GEOCOMP). Chapter 4 includes separate charts for the state files and the national file.
Chapter 7 includes the geographic ID file's record layout and a complete list of demographic data tables and data items. See Appendix A for definitions of geographic terms. It is recommended that GIS users also see notes on using boundary files.
Which data files within a data set to use
This section involves making a note of the file number(s) within a data set that contain specific tables of interest. Data files are numbered from 01 to 38. See Chapter 3 Subject Locator in the file documentation to identify table numbers of interest. See Chapter 2 How to Use This File Figure 2-2 to identify the data file(s) that contain these tables. See Chapter 7 Data Dictionary Table Matrix Section to see a complete list of data items contained in these tables. The complete table including the title, universe, all headings and data items is shown.
Which data sets (population groups) to use
This section involves making a note of the three digit code for each population group that you are interested in. See Appendix H. Characteristic Iterations from the file documentation for a list of population groups along with their codes. These codes appear in the CHARITER field of the data files.
Data file naming convention
This section involves using the information from the previous two sections to know which filenames you want to download. The data file directory will contain a long list of files named as shown below.
Geographic file (should be last in the list)
st is the state postal abbrieviation, ccc is the characteristic iteration code (CHARITER) and the last two digits is the data file number within the data set.
Example - If you are interested in table PCT01 (this table is in data file 01) for the Total Population and for Hispanic or Latino (of any race) for California and Oregon, you would download the following files from the California and Oregon directories : cageo, ca00101, ca40001, orgeo, or00101, or40001.
If you are interested in the same information for areas within the entire United States you would download usgeo, us00101, us40001 from the National directory. Note that the National file does not contain the exact same set of areas as the state files.
The steps above complete the data file selection process.
File documentation [, 5.32 MB]
Download Summary File 4 template file (Access 2000 format) provided here to get started. Next, open it in Microsoft Access™ and follow these procedures to import the ASCII data and attach the header (field name) information.
Download SAS programs or contact your local state data center (SDC) for an alternate version of the SAS ™ code. SPSS ™ code may also be available from your local SDC. The SAS programs convert the ASCII text data files to SAS data sets. Light modifications such as changing the input and output file names and the directories used to store data may need to be made.
SF4GEO.SAS - Converts the geographic identifier file
SF4xx.SAS - Converts the matching (by number) data file and merges this with SAS data set created by SF4geo.sas. There are thirty eight of these files numbered from SF401.sas to SF438.sas. Go to additional SAS instructions for more information.
This section assumes familiarity with operations in database management programs such as opening a data table and appending records to it as well as setting up a relationship between two data tables based on a common field.