The IPUMS National Historical Geographic Information System (NHGIS) provides free online access to summary statistics and GIS files for U.S. censuses and other nationwide surveys from 1790 through the present.
Through the NHGIS Data Finder, users may:
- Filter and sort through thousands of available tables and GIS files
- Select and download multiple tables and boundary files, for different geographic levels and from different years, all in one request
NHGIS does not provide tools for data analysis, mapping, or reporting. Rather, NHGIS supplies data files designed for use in spreadsheet applications (e.g., Microsoft Excel), statistical software (e.g., R, Stata, SPSS, SAS), or GIS applications (e.g., Esri ArcGIS, QGIS).
NHGIS is one of several IPUMS data integration projects housed (alongside the Minnesota Population Center) at the Institute for Social Research & Data Innovation at the University of Minnesota. The NHGIS project is funded by grants from the National Science Foundation and the Eunice Kennedy Shriver National Institute of Child Health and Human Development.
NHGIS highlights...
GIS files
- County and state boundaries since 1790
- Census tract boundaries since 1910
- Metropolitan area boundaries since 1950
- Block boundaries since 1970
- Place and county subdivision boundaries since 1980
- Boundaries for all standard census reporting areas since 1990
- Place points, 1900-2015
- Centers of population for states, counties, tracts, and block groups, 2000, 2010, & 2020
- Boundaries for three levels of hydrologic units
- SABINS school attendance areas (2009-10, 2010-11, & 2011-12 school years)
Summary tables
- Statistics from all decennial censuses and the American Community Survey
- County and state tables since 1790
- Census tract tables since 1910
- Tables for all original census summary levels, down to census blocks, since 1970
- County Business Patterns data (annual, 1970-2002)
- Vital statistics: births & deaths (1915-2007), marriages & divorces (1867-2010)
- Agricultural census data (1840-1950)
- Religious bodies data (1850-1952)
- Manufacturing census data (1840-1940)
- 2010 Census data for SABINS school attendance areas
Time series tables
- Comparable statistics from multiple censuses and the American Community Survey linked together with standardized categories and codes across time
- Two types of geographic integration:
- Nominally integrated tables link geographic units across time according to their names and codes
- Geographically standardized tables provide data from multiple times for a single census's units
- For more information, see the Time Series Table page
Supplemental data
- Geographic crosswalks for allocating data from one census's geographic units to another's (1990-2020)
- Environmental summaries, providing land cover and climate data for counties, census tracts, and some other levels, as well as estimates of census data for three levels of watersheds
- Annual census tract estimates, providing estimates of tract populations broken down by sex, age, and race for each year from 2000 to 2019
- Small-area summaries of the historical built environment, providing tract-level information about past characteristics of human settlement, including land use since 1940 and built-up extents since 1900, derived from the Historical Settlement Data Compilation for the US (HISDAC-US)
- Privacy-Protected 2010 Census Demonstration Data, which enable assessments of the 2020 Census Disclosure Avoidance System (DAS) by linking together original 2010 census summary tables with alternate versions based on different 2020 DAS models and parameters