Release Log

Two types of releases are documented: updates to the NHGIS website and updates to the NHGIS data (tabular or boundary data).

April 2014

Improved Breakdown Codes

NHGIS has made several improvements to its breakdown coding scheme. (See the FAQ for an explanation of NHGIS breakdowns.) The most significant changes:

  • Previously, breakdown codes in NHGIS data files were all 4 characters long. Now, to reduce noise in column identifiers, breakdown codes may be 2, 3, or 4 characters long depending on how many characters are needed to uniquely identify all breakdown combinations in use by a given dataset.
  • Previously, the ordering of codes was somewhat arbitrary, determined by the sequence of breakdowns in the NHGIS metadata database. Now, codes are ordered according to their original logical sequence.
  • Previously, in multi-year datasets like County Business Patterns, codes varied by both breakdown and year, so a single industry breakdown category would have different codes in different years. Now, within each dataset, a breakdown has a single code across all years, making it easier to identify files and columns associated with the same breakdown.

Note: as a consequence of these updates, most breakdowns have new codes. Users who would like to re-obtain previous data requests with codes that match the current codes may simply resubmit their older requests through the Extracts History page.

February 2014

Time Series Tables, Release 4.1

This release updates all tables that include American Community Survey (ACS) data to use 2012 5-year data instead of 2011 5-year data.

Because the 2008-2012 period is centered on the year 2010, we believe it is the most suitable ACS period for use in the NHGIS's decade-interval time series. Therefore, this update should be the last of its kind. NHGIS may in the future release new time series tables that include ACS data from other time periods, but there are no plans to again swap old data with new.

For almost all time series, there are 2012 ACS statistics that correspond exactly to the previously used 2011 ACS statistics, with one exception. It was not possible to extend the time series of persons born in (former) Yugoslavia because the 2012 ACS Summary Files provide no separate count of persons born in Yugoslavia.

Accordingly, for effective comparability, the (former) Yugoslavia time series is now provided in a new, separate table named "Persons Born in (Former) Yugoslavia," which is the only time series table to use 2007-2011 ACS data. In the 6 place-of-birth tables that had previously provided a distinct count for (former) Yugoslavia, the subgroup is now included within "Other Europe" or "Other Eastern Europe" counts, as appropriate for each table.

Also in this release, the table of "Persons 16 Years and Over by Labor Force and Employment Status [6]" has been extended to cover tracts, county subdivisions, and places.

2012 ACS 5-Year Summary File Release

The 2012 American Community Survey (ACS) 5-Year Summary File has been released on NHGIS. Over 1,000 tables offer detailed cross-tabulations of age, sex, race, household structure, housing units, income, education, transportation, and many other topics. This 2012 ACS release also includes tables on health insurance coverage. This is the first time the topic has been available in a 5-Year ACS.

In the 5-year dataset, tables are available at the block group geographic area and larger.  

Users should be aware that NHGIS has modfied the original format of the ACS data to replace "." jam values with blanks for files in the comma delimited (.csv) output format. This was done to facilitate GIS processing. These jam values appear within certain tables for records with too few observations to tabulate. Users interested in obtaining the original "." values should request data in the fixed width format when finalizing their data extracts. Additional information on jam values can be found within the 2012 ACS technical documentation.
 

December 2013

Revised and New GIS Boundary Files

NHGIS has released updated GIS Boundary files that reflect various, small coastline revisions made by NHGIS. All 2010 and 2011 GIS Boundary files with a basis of TIGER/Line 2010+ or TIGER/Line 2011+ are included in this update except those state-specific block and block group GIS boundary files for the non-coastal states.   

NHGIS has also released a new 2011 nationwide block group file to correspond with the preexisting 2011 state-specific block group files, as well as 2012 state-specific block group files to correspond with the preexisting 2012 nationwide block group file.   

In addition, this release includes a boundary file for the newly defined 2010 Public Use Microdata Areas (PUMAs). The file is derived from 2012 TIGER/Line files and corresponds to tabular data from the 2012 American Community Survey (ACS). Note that PUMA statistics from the 2010 and 2011 ACS datasets use the older 2000 PUMA definitions. At this time, the U.S. Census Bureau has not released any 2010 Census summary statistics for PUMAs.
 

November 2013

2012 ACS 3-Year Summary File Release

The 2012 American Community Survey (ACS) 3-Year Summary File has been released on NHGIS. Over 1,400 tables offer detailed cross-tabulations of age, sex, race, household structure, housing units, income, education, transportation, and many other topics.

In the 3-year dataset, tables are available for geographic areas exceeding the U.S. Census Bureau minimum population requirement of 20,000 persons.

Users should be aware that NHGIS has modfied the original format of the ACS data to replace "." jam values with blanks for files in the comma delimited (.csv) output format. This was done to facilitate GIS processing. These jam values appear within certain tables for records with too few observations to tabulate. Users interested in obtaining the original "." values should request data in the fixed width format when finalizing their data extracts. Additional information on jam values can be found within the 2012 ACS technical documentation.

2012 GIS Boundary Files

NHGIS has released new GIS boundary files based on 2012 TIGER/Line Shapefiles. The new files correspond to the already released 2012 American Community Survey 1-Year dataset and the soon-to-be released 3- and 5-Year datasets. The release consists of 34 nationwide files for these geographic levels:

  • 5-Digit ZIP Code Tabulation Area (ZCTA)
  • Alaska Native Regional Corporation
  • American Indian Area/Alaska Native Area/Hawaiian Home Land (in 3 formats: all areas; reservation or statistical entity only; and off-reservation trust and home lands only)
  • Block Group
  • Census Tract
  • Combined Statistical Area
  • Congressional District (112th Congress)
  • Congressional District (113th Congress)*
    *internal boundaries derived from the special 113th Congressional District TIGER/Line Files; coastlines derived from the 2012 TIGER/Line Files
  • Consolidated City
  • County
  • County Subdivision
  • Division
  • Metropolitan Division
  • Metropolitan Statistical Area/ Micropolitan Statistical Area
  • Nation
  • New England City and Town Area (and Combined NECTA and NECTA Division files)
  • Place
  • Region
  • School Districts (Unified, Elementary and Secondary files)
  • State
  • State Legislative Districts (Lower Chamber and Upper Chamber files)
  • Subminor Civil Division
  • Tribal Block Groups, Tribal Census Tracts, and Tribal Subdivisions
  • Urban Area
  • Voting District

2000 GIS Boundary Files Derived from 2010 TIGER/Line Files

NHGIS has released new GIS boundary files for 2000 census areas that are based on 2010 TIGER/Line Shapefiles. The 71 new files are more spatially accurate than the shapefiles based on 2000 TIGER/Line files due to the Census Bureau’s MAF/TIGER Accuracy Improvement Project. The complete list of geographic levels covered includes:

  • 5-Digit ZIP Code Tabulation Area (ZCTA)
  • Alaska Native Regional Corporation
  • American Indian Area/Alaska Native Area/Hawaiian Home Land (in 3 formats: all areas; reservation or statistical entity only; and off-reservation trust and home lands only)
  • Block (51 separate state-extent files, including the District of Columbia)
  • Block Group
  • Census Tract
  • Congressional District (108th Congress)
  • Consolidated City
  • County
  • County Subdivision
  • Division
  • Nation
  • Place
  • Region
  • State
  • State Legislative Districts (Lower Chamber and Upper Chamber files)
  • Tribal Subdivision
  • Voting District
     

October 2013

New "Popularity" Bars

A new "Popularity" column in the NHGIS Data Finder's "Select Data" section contains bars that represent the relative usage rates of NHGIS data tables and boundary files. The "popularity" is measured as the number of NHGIS users who have requested each table or file, with each user weighted in proportion to how recently their last request was made.

NHGIS users may now inspect the popularity bars and sort available data by popularity in order to identify quickly the tables and files that are of greatest interest to the NHGIS community.

Time Series Tables, Release 4.0

Release includes 47 new tables for 10 tabulation types:

  • 1 table: Median Age of Persons
  • 1 table: Median Age of Persons by Sex
  • 12 tables: Persons by Nativity by Place of Birth
  • 5 tables: Persons by Labor Force, Employment and Armed Forces Status (by Age)
  • 6 tables: Persons by Labor Force, Employment and Armed Forces Status by Sex (by Age)
  • 5 tables: Persons by Educational Attainment
  • 7 tables: Persons by Educational Attainment by Sex (by Age)
  • 4 tables: Households by Income in Previous Year
  • 4 tables: Families by Income in Previous Year
  • 1 table: Median Family Income in Previous Year
  • 1 table: Per Capita Income in Previous Year

2012 ACS 1-Year Summary File Release

The 2012 American Community Survey (ACS) 1-Year Summary File has been released on NHGIS. Over 1,400 tables offer detailed cross-tabulations of age, sex, race, household structure, housing units, income, education, transportation, and many other topics.

In the 1-year dataset, tables are available for geographic areas exceeding the U.S. Census Bureau minimum population requirement of 65,000 persons.

Users should be aware that NHGIS has modfied the original format of the ACS data to replace "." jam values with blanks for files in the comma delimited (.csv) output format. This was done to facilitate GIS processing. These jam values appear within certain tables for records with too few observations to tabulate. Users interested in obtaining the original "." values should request data in the fixed width format when finalizing their data extracts. Additional information on jam values can be found within the 2012 ACS technical documentation.
 

August 2013

New "Time Varies by Column" Layout for Time Series

NHGIS now provides a third layout option for time series tables in addition to the existing options of "time varies by file" and "time varies by row." The new "time varies by column" option places data for different times in separate columns within one file. For example, a table of state-level 2000 and 2010 census data is delivered in one file with one row for each state and two columns for each time series: one column for 2000 and one column for 2010.
 

NOTE: this layout matches area units across time according to area names and codes only without regard to geographic relationships. A single row may provide statistics for distinctly different areas at different times in cases where a matched code refers to distinct areas at different times.

Improved Topic Filtering

NHGIS systematically revised and verified its topic filtering system. The new set of selectable topics more closely and completely represents the topics available in NHGIS data. We also thoroughly reviewed associations between topics and tables to help ensure that all relevant tables--and only relevant tables--appear for any selected topics.

 

May 2013

2011 GIS Boundary Files 

NHGIS has released 2011 GIS boundary files, based on 2011 TIGER/Line Shapefiles from the U.S. Census Bureau. The 81 new shapefiles correspond to the 2011 American Community Survey 1, 3, and 5-Year datasets. The release includes statewide shapefiles for block groups and nationwide files for many other larger geographic levels. The complete list of levels includes:

  • Alaska Native Regional Corporation
  • American Indian Area/Alaska Native Area/Hawaiian Home Land (in 3 formats: all areas; reservation or statistical entity only; and off-reservation trust and home lands only)
  • Block Group (52 separate state-extent files, including the District of Columbia and Puerto Rico)
  • Census Tract
  • Combined Statistical Area
  • Congressional District (112th Congress)
  • Consolidated City
  • County
  • County Subdivision
  • Division
  • Metropolitan Division
  • Metropolitan Statistical Area/ Micropolitan Statistical Area
  • Nation
  • New England City and Town Area (and Combined NECTA and NECTA Division files)
  • Place
  • Region
  • School Districts (Unified, Elementary and Secondary files)
  • State
  • State Legislative Districts (Lower Chamber and Upper Chamber files)
  • Subminor Civil Division
  • Tribal Block Groups, Tribal Census Tracts, and Tribal Subdivisions

Unified NHGIS Shapefiles

NHGIS shapefiles, for all geographic levels larger than block group, have been streamlined by merging previously separated Contiguous U.S., Alaska, Hawaii, and Puerto Rico shapefiles into a single U.S. shapefile with a single projection, the USA Contiguous Albers Equal Area Conic. Because pre-1880 shapefiles do not include areas for Alaska, Hawaii, or Puerto Rico, they were not affected by this change.

Historical County Shapefile Corrections

1880 and 1910 county shapefiles were modified, in each case removing a county record to reflect how census data were originally reported.

Error 1: The 1880 county shapefile had a polygon for newly formed Dickenson County, VA, but that county was not recognized in most original census tables, and the population for its area was reported for Wise and Buchanan Counties (out of which Dickenson was carved).
Correction 1: The 1880 shapefile was changed to match 1870 boundaries in this area, in effect deleting Dickenson County from the 1880 file.

Error 2: The 1910 county shapefile had a polygon for newly formed Greenlee County, AZ, but its population was reported with Graham County, AZ, from which Greenlee had been created.
Correction 2: The 1910 shapefile was changed to match the1900 boundaries in this area, in effect deleting Greenlee County from 1910 file.

April 2013

Time Series Tables, Release 3.0

Release includes 9 new tables for 3 tabulation types that principally use sample-based data, including, for the first time, 2007-2011 American Community Survey data:

  • Persons by Marital Status by Sex (by Age)
  • Persons by Nativity
  • Median Household Income in Previous Year

In addition, 3 existing tables now provide data from the 2007-2011 ACS as well as from the 2010 Census. The complete list of new or expanded time series tables: 

Table Name Years Geographic Levels
Total Population 1970, 1980, 1990, 2000, 2010, 2007-2011 state, county, cty_sub, tract, place
Total Population 1980, 1990, 2000, 2010, 2007-2011 nation, region, division, state, county, cty_sub, tract, place
Persons by Sex [2] 1970, 1980, 1990, 2000, 2010, 2007-2011 state, county, cty_sub, tract, place
Persons of Marrying Age* by Sex [2] by Marital Status [6] 1970, 1980, 1990, 2000, 2007-2011 state, county, cty_sub, tract, place
Persons of Marrying Age* by Sex [2] by Marital Status [8] 1970, 1990, 2000, 2007-2011 state, county, cty_sub, tract, place
Persons of Marrying Age* by Sex [2] by Marital Status [5] by Age [7] 1970, 1980, 1990, 2000, 2007-2011 state, county, cty_sub
Persons of Marrying Age* by Sex [2] by Marital Status [5] by Age [7] 1970, 2000, 2007-2011 state, county, cty_sub, tract, place
Persons 15 Years and Over by Sex [2] by Marital Status [5] by Age [11] 1980, 1990, 2000, 2007-2011 nation, region, division, state, county, cty_sub
Persons 15 Years and Over by Sex [2] by Marital Status [5] by Age [12] 1990, 2000, 2007-2011 nation, region, division, state, county, cty_sub
Persons 15 Years and Over by Sex [2] by Marital Status [6] by Age [12] 2000, 2007-2011 nation, region, division, state, county, cty_sub, tract, place
Persons by Nativity [2] 1970, 1980, 1990, 2000, 2007-2011 state, county, cty_sub, tract, place
Median Household Income In Previous Year 1980, 1990, 2000, 2007-2011 nation, region, division, state, county, cty_sub, tract, place

 

Time Series Tables, Release 2.0

Release includes 18 new tables: 8 tables for tabulation types first covered in Release 1.0 and 10 tables for these newly covered tabulation types:

  • Persons by Urban/Rural Status
  • Persons by Hispanic or Latino Origin by Sex by Age
  • Total Households
  • Households by Household Type by Household Size
  • Total Families
  • Housing Units by Urban/Rural Status

The complete list of new Release 2.0 time series tables: 

Table Name Years Geographic Levels
Total Population 1980, 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Persons by Urban/Rural Status [2] 1970, 1980, 1990, 2000, 2010 state, county, cty_sub, place
Persons by Urban/Rural Status [4] 1980, 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Persons of Some Other Race* by Age [5] 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Persons by Hispanic or Latino Origin [26] 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Persons of Hispanic or Latino Origin by Sex [2] by Age [5] 1980, 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Persons of Hispanic or Latino Origin by Sex [2] by Age [22] 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Total Households 1970, 1980, 1990, 2000, 2010 state, county, cty_sub, tract, place
Households by Household Type [2] by Household Size [7] 1980, 1990, 2000, 2010 state, county, cty_sub, place
Total Families 1970, 1980, 1990, 2000, 2010 state, county, cty_sub, tract, place
Persons Under 18 Years In Households by Household Relationship [5] by Age [7] 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Rural Housing Units 1970, 1980, 1990, 2000, 2010 state, county, cty_sub, place
Housing Units by Urban/Rural Status [4] 1980, 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Occupied Housing Units by Tenure [3] 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Occupied Housing Units by Race of Householder [6*] 1980, 1990, 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Occupied Housing Units by Race of Householder [7] 2000, 2010 nation, region, division, state, county, cty_sub, tract, place
Occupied Housing Units by Tenure [2] by Household Size [6] 1970, 1980, 1990, 2000, 2010 state, county, cty_sub, tract, place
Occupied Housing Units by Tenure [2] by Household Size [7] 1970, 1990, 2000, 2010 state, county, cty_sub, tract, place

 

February 2013

Realigned GIS Boundary Files

Because the Census Bureau made major accuracy improvements to TIGER/Line features between the 2000 and 2008 TIGER/Line releases, the original NHGIS shapefiles based on 2000 TIGER/Line features are not comparable with newer TIGER/Line data. We therefore generated new 2008-based boundary files by systematically realigning the boundaries for tracts and counties to fit with 2008 TIGER/Line features. Most of these realigned boundaries also align properly with 2010 and later TIGER/Line files, but note that the 2008-based boundaries include occasional gross inaccuracies that the Census Bureau corrected in later TIGER/Line files.

Additional information on the various NHGIS boundary file versions can be found on the GIS Boundary Files documentation page here.

 

January 2013

2011 ACS 1, 3 & 5-Year Summary File Release

The 2011 American Community Survey (ACS) 1, 3 & 5-Year Summary Files have been released on NHGIS. Over 3,800 tables offer detailed cross-tabulations of age, sex, race, household structure, housing units, income, education, transportation, and many other topics.

In the 1-year dataset, tables are available for geographic areas exceeding the U.S. Census Bureau minimum population requirement of 65,000 persons.

In the 3-year dataset, tables are available for geographic areas exceeding the U.S. Census Bureau minimum population requirement of 20,000 persons.

In the 5-year dataset, tables are available for most geographic levels, ranging from the nation down to block groups, with no general minimum population requirement.

Users should be aware that NHGIS has modfied the original format of the ACS data to replace "." jam values with blanks for files in the comma delimited (.csv) output format. This was done to facilitate GIS processing. These jam values appear within certain tables for records with too few observations to tabulate. Users interested in obtaining the original "." values should request data in the fixed width format when finalizing their data extracts. Additional information on jam values can be found within the 2011 ACS technical documentation.

At this time, 2011 GIS shapefiles are not yet available on NHGIS. However, 2011 ACS data will join with existing 2010 shapefiles for most geographic levels with little or no complication.

 

December 2012

 2010 Summary File 2 Release

NHGIS has released 71 tables which make up the 2010 Summary File 2 release. These tables, available at the census tract and higher geographic levels, include 330 different race/ethnicity breakdowns.  For additional information, please review the technical documentation found here.

 

October 2012

Urban/Rural Update to 2010 Summary File 1

NHGIS has released the 2010 Summary File 1 Urban/Rural Update File.  This update adds urban area-related geographic levels, new urban/rural tables, and urban/rural breakdown values for other SF1 tables.

Time Series Tables, Release 1.1

8 new tables for the same tabulation types and years covered by Release 1.0. Also includes some revisions to existing tables to expand their coverage of geographic levels.

 

September 2012

Time Series Tables, Release 1.0

114 tables for the following tabulation types, designed to cover as many years and categories as is possible for the period 1970-2010:

  • Total Persons*
  • Persons by Sex*
  • Persons by Age
  • Persons by Sex by Age
  • Persons by Race
  • Persons by Sex by Race
  • Persons by Race by Age
  • Persons by Sex by Race by Age
  • Persons by Hispanic or Latino Origin
  • Persons by Hispanic or Latino Origin by Race
  • Persons by Household, Family and Group Quarter Type
  • Persons by Household and Group Quarter Type by Sex
  • Persons by Household and Group Quarter Type by Age
  • Persons by Household and Group Quarter Type by Sex by Age
  • Persons by Household Type by Relationship to Householder
  • Persons by Household Type by Relationship to Householder by Age
  • Persons by Housing Tenure
  • Families by Presence of Own Children Under 18 Years by Family Type by Age Groups of Children
  • Total Housing Units
  • Housing Units by Occupancy Status/Vacancy Status/Tenure
  • Housing Units by Tenure by Household Size
  • Housing Units by Tenure by Race of Householder

*Includes a Total Persons time series for 1790-2010 and Persons by Sex time series for 1820-2010.

For additional information, see the Time Series Documentation page.

 

July 2012

2008-2010 American Community Survey 3-Year data release

The 2010 American Community Survey (ACS) 3-Year Summary File has been released on NHGIS. Over 1,400 tables offer detailed cross-tabulations of age, sex, race, household structure, housing units, income, education, transportation, and many other topics. Data is available at several geographic levels for those areas exceeding the minimum population requirement of 20,000 for 3-year ACS datasets.

Users should be aware that NHGIS has modfied the original format of the ACS data to replace "." jam values with blanks for files in the comma delimited (.csv) output format. This was done to facilitate GIS processing. These jam values appear within certain tables for records with too few observations to tabulate. Users interested in obtaining the original "." values should request data in the fixed width format when finalizing their data extracts. Additional information on jam values can be found within the 2010 3-Year Summary File technical documentation.

 

May 2012

2006-2010 American Community Survey 5-Year data release

The 2010 American Community Survey (ACS) 5-Year Summary File has been released on NHGIS. Over 900 tables offer detailed cross-tabulations of age, sex, race, household structure, housing units, income, education, transportation, and many other topics. Data is available at geographic levels ranging from the nation down to block groups.

Users should be aware that NHGIS has modfied the original format of the ACS data to replace "." jam values with blanks for files in the comma delimited (.csv) output format. This was done to facilitate GIS processing. These jam values appear within certain tables for records with too few observations to tabulate. Users interested in obtaining the original "." values should request data in the fixed width format when finalizing their data extracts. Additional information on jam values can be found within the 2010 5-Year Summary File technical documentation.

 

April 2012

2010 American Community Survey 1-Year data release

The 2010 American Community Survey (ACS) 1-Year Summary File has been released on NHGIS. Over 1,400 tables offer detailed cross-tabulations of age, sex, race, household structure, housing units, income, education, transportation, and many other topics. Data is available at several geographic levels for those areas exceeding the minimum population requirement of 65,000 for 1-year ACS datasets.

Users should be aware that NHGIS has modfied the original format of the ACS data to replace "." jam values with blanks for files in the comma delimited (.csv) output format. This was done to facilitate GIS processing. These jam values appear within certain tables for records with too few observations to tabulate. Users interested in obtaining the original "." values should request data in the fixed width format when finalizing their data extracts. Additional information on jam values can be found within the 2010 1-Year Summary File technical documentation.

 

January 2012

Table errors corrected

A number of tables were recently discovered to have erroneously excluded decimal points or “multipliers”. These tables ranged from years 1790 to 2010, and all geographic levels were affected. All tables have been corrected and are listed below (Adobe PDF and Microsoft Excel). Users may choose to “resubmit” their extract on the Extracts History page to receive fixed data or may simply modify the data themselves by adding the decimal place or multiplier. Data downloaded through the new NHGIS data extract system between October 11, 2011 and January 10th, 2012  will include erroneous values.

The implied decimal tables displayed a whole number that needed one or two decimal places instead. For example, a table of Median Age may have shown a value of 297 years while the true value is 29.7 years.

The implied multiplier tables displayed a value that needed to be multiplied by a constant to arrive at the true value. For example, a table on Payroll of Selected Establishments may have a value of $673 while the true value is $673,000 as it has a multiplier of 1,000. Other multipliers include 10 and 250.

NHGIS apologizes for any inconvenience or confusion this may have caused our valued users.

List of Implied Decimal tables - (.xlsx) (.pdf)

List of Implied Multiplier tables - (.xlsx) (.pdf)
 

2010 Summary File 1 data release

NHGIS is pleased to announce that 2010 Census Summary File 1 is now available for download. Summary File 1 includes 331 tables that offer detailed cross-tabulations of age, sex, race, household structure, housing units, and other related topics.

Most tables are tabulated at many geographic levels, ranging from the national level down to the block level.

 

October 2011

A new website and new 2010 data!

The NHGIS website has been completely redesigned to provide a range of new features making it easier to find and acquire data. Users can specify a set of data filters, in any combination, to narrow the thousands of tables down to just those they want. It is also possible to select and download data for any number of years, topics or geographic levels all at once.

Over the next year, NHGIS will also be expanding to include data from the 2010 Census and the American Community Survey, beginning with the 2010 PL 94-171 Redistricting Data, available now through the new website! Be sure to check back often for new data, site features, tutorials and documentation as we continue through several phases of planned site improvements.

 

April 2011

New School Attendance Boundaries data

The School Attendance Boundary Information System (SABINS) is a new NSF-funded infrastructure project that consists of Geographic Information System (GIS) files delineating elementary, middle and high school attendance catchment areas embedded in the largest school districts in the United States. All GIS files are for the 2009-2010 school year and can be downloaded for free from the National Historical GIS (NHGIS). There are 13 grade-specific GIS files of school catchment areas, one for each grade (Kindergarten through 12th). SABINS data have been released for all K-12 school catchment areas in Delaware, Minnesota, and Oregon and for all school districts embedded in a wide variety of Metropolitan Statistical Areas. For further details regarding the school districts that will be included in the SABINS database, please email sabins@wm.edu.

Every grade-specific school attendance boundary is associated with tabular data from two sources. The first is the 2010 Census Redistricting Data that enumerates the number of people in each school catchment area by race and age. In the coming months SABINS will release more detailed population characteristics for the school catchment areas. These data will be derived from the five-year American Community Survey data. SABINS will provide ACS estimates describing socioeconomic variables for school catchment areas. The second data source to which school attendance boundaries can be linked are the U.S. Department of Education's Common Core of Data (CCD). The CCD consists of information describing the characteristics of public schools that serve each school attendance boundary, including enrollment by grade, race, gender, and free or reduced-price lunch status. School-level standardized test score data from the Amerian Institutes for Research can also be downloaded and linked to each school and school catchment area.

 

May 2008

1990 census block summary data (STF1) have been added

Also, data were corrected in the 1970 County file (CNG4H). 

 

April 2008

New release of GIS boundary files 

The files now include a new GISJOIN field to be used for joining attribute data retrieved from NHGIS.  The new GISJOIN field is saved as a string field.  The older GISJOIN (now GISJOIN2) field was preserved.  The following GIS boundary files were updated:

  • American Indian area, Alaska Native area, Hawaiian home land
  • AITS
  • Block
  • Block Group
  • Congressional District
  • Consolidated Metropolitan Statistical Area
  • County
  • County Subdivision
  • Minor Civil Division
  • Metropolitan Statistical Area / Consolidated MSA
  • New England County Metropolitan Area
  • Place
  • Primary Metropolitan Statistical Area
  • Standard Consolidated Statistical Area
  • Standard Metropolitan Statistical Area
  • State
  • Census Tract (includes 1980 Block Numbering Areas)
  • Trust Land
  • Urban Area
  • Voting District
  • Zip Code Tabulation Area

Also, the following files have two new fields available in the shape file:  SHAPE_LEN and SHAPE_AREA:

  • Consolidated Metropolitan Statistical Area
  • Metropolitan Statistical Area / Consolidated MSA
  • Primary Metropolitan Statistical Area
  • Standard Consolidated Statistical Area
  • Standard Metropolitan Statistical Area

 

March 2008

New 1980, 1990 and 2000 boundary files released

Using the 1992 TIGER file, the following boundary files were created and released:

  • 1980 Minor Civil Divisions
  • 1980 Place
  • 1980 Block Numbering Areas (Packaged within the census tract files)
  • 101 and 103 Congressional District

*Please note – due to some data corruption in the original 1992 TIGER file, some areas of the country could not be extracted and released.*

Using the 2000 TIGER-LINE UA file, the following files were created and released:

  • 1990 and 2000 American Indian area/Alaska Native area/Hawaiian home land
  • 2000 American Indian Tribal Subdivision
  • 1990 and 2000 Census Block Groups
  • 1990 and 2000 Census Blocks
  • 106 Congressional District
  • 1990 and 2000 County Subdivision
  • 1990 and 2000 Places
  • 2000 Trust Lands
  • 1990 and 2000 Urban Areas
  • 1990 and 2000 Voting Districts
  • 2000 ZIP Code Tabulation Areas (ZCTAs)

 

April 2007

Updated NHGIS site released. The new site revised many of the static documentation areas, but the statistical and mapping extraction tools remained unchanged.

 

December 2004

Released the first public beta version of the Data Access System. The system was released with data from the 1990 Federal Census of Population and Housing, including Summary Tape Files 1, 2, 3 and 4. NHGIS is the first system to make the highly detailed historical data contained in 1990 STF 2 and 4 easily accessible on the web.

 

November 2004

Released an internal beta version of the Data Access System to NHGIS collaborators and advisory board members for testing.