This page contains links to products from 1990 Census that are available at Columbia or on public Internet sites. The access methods are those currently available; methods that have improved since the 1990 files were released. References to documentation developed at that time are also provided.

Data Sources	Overview of Products	General Information
Online Data Extraction GIS Products CD-ROM Products Files for FTP	Summary Files Public Use MicroData Maps and Spatial Data	Census Bureau Site Comparing 1990 and with other Census years Library's Collection

Data Sources and Software

• Online Data Extraction
  
  • American FactFinder
    Access to STF1 and STF3 for all levels of geography, is offered at this site. Multiple data tables for multiple locations at one level of geography can be downloaded at one time.
  • Infoshare Online
    Access to STF1A, STF3A, and Public Use Microdata is available. For STF files, a single data table for a multiple locations can be downloaded. Locations include geographies unique to New York City, like Community District. For Public Use Microdata, you can cross tabulate two variables.
  • Integrated Public Use Microdata Series (IPUMS)
    At this site custom extractions of public use microdata can be done. Coverage is for all census years since 1850 except 1930.
  • National Historical Geographic Information System (NHGIS)
    Provides an online extraction tool for selected summary file variables at the national, state, county, tract/block numbersing area, metropolitan area, and primary metropolitan area levels allowing for multiple locations at one level of geography to be downloaded at once. Downloads of a single area for other census geographies are available.
  
   
• GIS Products
  • TIGER/Line®
    The files are available on CD-ROM in EDS for 1994, 1995, and 1998. Meta data about these files is available at the Census Bureau Web site. The 1992 file, which is also available on CD-ROM in EDS, (recommeded only for those doing a comparison to 1980) can be downloaded from the Census Bureau Web site
  • Cartographic Boundary Files
    Cartographic boundary files are a generalized extract from the U.S. Census Bureau's TIGER® database. Files in ARC/INFO Export (.e00), Arcview Shapefile, and ARC/INFO Ungenerate (ASCII) are available.
  • Archive of Census Related Products
    Maintained by the Center for International Earth Science Information Network (CIESIN), this ftp archive is a collection of georeferenced data files containing census information that spans the United States.
  • National Historical Geographic Information System (NHGIS)
    NHGIS is a project to create and freely disseminate a database incorporating all available aggregate census information for the United States between 1790 and 2000. You can download tract boundary files by state
  • Wessex CD-ROMs
    Wessex files are geographic files which enable users to create maps with 1990 Census boundaries using the Mapinfo program.

 
• CD-ROM Products in the EDS Collection
  
  • Geolytics CD-ROM Products
    These products come with easy-to-use software that extract data for use in statistical packages, for making thematic maps, or for importing in to GIS software. Guides for using Geolytics are available.
    • 1990 CensusCD+Maps
      (data to the block group level, includes ZIP codes)
    • 1990 Blocks (block level data)
    • Neighborhood Change Database (reports 1990 data using 2000 tract boundaries)
  • CD-ROMs from the Federal Government
    Refer to 1990 Census --CD-ROMs for alist ofthese CD-ROMs. Guides are still available for these products and the early software interfaces for using them.
    • Summary Tape Files
      These are in .dbf, an ASCII fixed length format. All the summary files on this list can be used with the GO software that comes on the disc, by SAS and SPSS, and by the Extract software that was at one time needed for large extracts.
    • Public Use Microdata (PUMS)
      These are in ascii format and duplicate what is stored on Cunix.
    • Other products
      The EEO files uses GO software and the CTTP come with their own custom extraction software.

 
• Files for FTP
  • DataGate
    Searching DataGate for EDS Study #1990 will return a list of all holdings whether they are available for downloading from the Cunix or in another format. Files for the local areas are stored on Cunix along with SAS and SPSS program code for these files.
  • ICPSR
    This link leads to the complete list of what ICPSR provides. Use this source if you do not find what you are looking for in DataGate. Like DataGate, data is in the format of the original tape files, one geared for processing by statistical software.
  • Census Bureau FTP Site
    This public site allows for downloading the STF1, STF3, and selected data from STF4. The STF1 and STF3 files are derived from the CD-ROM versions of these files that have a record structure different from the original tape files.

An Overview of Data Products

• Summary Tapes Files

  Summary Tape Files report data tabulated to various geographic levels, referred to on the files as "summary levels." The files are organized based on their geographic coverage and on whether they include topics based on questions from the long form questionnaire (files STF1 is based solely on the topics covered on the short form, while STF3 and STF4 included topics from both the long form and the short form).

  STF1      A: States - Block Groups      B: Blocks      C: Nation-Counties      D: Congressional Districts

  STF3      A: States - Block Groups      B: Zip Codes      C: Nation-Counties      D - Congressional Districts

  STF4 Summary Tape File 4 reports the same topics as STF3 but, for it's cross tabulations, uses detailed race and hispanic categories rather than the basic ones. STF4A covers States - Block Groups, and STF4C covers Nation - to areas of 10,000 or more.

  Public Law (P.L.) 94-171 Also called the Redistricting file, it was the first file published from the 1990 Census and was used for congressional reapportionment. Data is based on the short form and focuses on age, sex, race, and Hispanic origin.

  SSTF Subject Summary Tape Files analyze a topic (like ancestry, education, etc.) or population (blacks, asians, etc). Cross tabulations within these files are reported at the national level only.


 
• Public Use Microdata (PUMS)
  PUMS files contain records for a sample of housing units with information on the characteristics of each unit and each person in it. They represent individual long form questionnaire responses. While preserving confidentiality (by removing identifiers), these microdata files permit users with special needs to prepare virtually any tabulation. Two samples are available, a 1% sample and a 5% sample, and both are issued by state. The basic geographic level for reporting on each is a Public Use Microdata Area (PUMA). PUMAs, which are defined differently on the two samples, have a minimum size of 200,000 persons. The PUMAs in the 1-Percent Sample are based on a distinction between metropolitan and nonmetropolitan areas and may cross state boundaries. The PUMAs in the 5-Percent Sample are based on counties and places within states.

 
• Maps and Spatial Data
  
  • TIGER/Line®
    The geographic boundaries used in the 1990 Census are described on the TIGER/Line® files. These files are not graphic images of maps, but rather digital data describing geographic features. To make use of these data, a user must have mapping or Geographic Information System (GIS) software that can import TIGER/Line® data.
  • Printed Maps
    The Census Bureau distributed Census maps in print. EDS has the Tract Boundary Maps and the Puma maps for 1990.

 
• Other Products
  The Census Bureau publishes two special tabulations that it prepares under contract for other agencies: Equal Employment Opportunity (EEO) File and the Census Transportation Planning Package (CTTP) file.

General Information

• 1990 Census Web Site
  This site brings together all the data products and documentation maintained by the Census Bureau.

 
• Obtaining Data by Congressional District

 
• Comparing 1990 and with other Census years
  • Geographic Correspondence Engine
    An interactive Web site that will generate correlations among 1990 Census boundaries, Zip codes, and 1980 boundaries.
  • Significant Changes to Counties: 1970-Present
    Summarizes the changes to boundaries for counties or county equivalent areas deemed to be significant because of either population affected or land area involved.
  • Comparing 1990 and 2000
    Links to information about comparing subject and geographies between these two years.
  • Tract Comparison Tables, New York City
    Excel spreadsheets that cover the tract changes between 1970-1980-1990-2000.

 
• Guides to using Geolytics Products:
  • CensusCD Blocks at EDS
  • CensusCD+Maps at EDS (brief html version)
  • CensusCD+Maps at EDS (long PDF format)
  • CensusCD Geography and Data Information
  • Neighborhood Change DataBase at EDS

 
• Library's Collection
  This is a detailed list of Columbia's print and CD-ROM holdings plus links to useful Web sites and reference sources.