Project Features Summary

  Data structure Temporal scope Geographic scope Geographic detail GIS files Collection instrument
USA Microdata 1850 - present U.S. 1950-present: PUMA/county group, select counties, select metros
1940 & earlier: County, city, ward
Separate download
Decennial Census & ACS
NHGIS Aggregate 1790 - present U.S.

1970-present:    Block (decennial census) or block group (ACS)
1910-1960: Census tract
Prior to 1910: County

Via extract system
Decennial Census & ACS, also includes data from other sources
International Microdata 1850 - 1911;
1960s - present
100+ countries Second administrative level1,2 Separate download
Population & housing censuses. Labor force surveys
IHGIS Aggregate 1960s - present 100+ countries Second or third adminstrative level1 Separate download
Population & housing censuses. Agricultural censuses & surveys
CPS Microdata 1962 - present U.S. State, metro, select counties, select cities n/a Monthly labor force survey of households. Also includes rotating supplemental topics
Time Use Microdata 1965 - present 14+ countries U.S. samples: State, select counties, select metros
International samples: Region (country-specific)
n/a ATUS: Individual 24-hour time diary survey.
AHTUS & MTUS: Time diary surveys.
NHIS Microdata 1963 - present U.S. Census region
2001 & earlier: Large metros
n/a Self-reported health survey of civilian, non-institutionalized population. Level of detail on household members varies by survey year.
MEPS Microdata 1996 - present U.S. Census region n/a Health and medical expenditure short panel survey. Sampling frame is households selected for the NHIS.
DHS Microdata 1980s - present 40+ countries First administrative level1,3 Separate download
Survey of women of childbearing age, includes information on their young children and births. Also covers all members of randomly sampled households and, in many cases, adult men.
PMA Microdata 2010s - present 10+ countries First administrative level1,4 Separate download
Surveys of women of childbearing age and their households. Associated surveys of family planning and other health service delivery points.
HigherEd Microdata 1993 - 2013 U.S. None n/a Surveys of college and doctoral graduates, focused on science and engineering (STEM) workforce.
Terra Microdata, Aggregate, Raster 1960s - present 100+ countries Second administrative level1,2 Via extract system Population & housing censuses. Raster data from satellite imagery, weather stations, and other sources.

1 Administrative levels represent the sub-national units into which countries are divided. They are usually hierarchical, with second level units nesting within first level parent units. For example, in the United States, states are first level administrative units and counties are second level administrative units.

2 In IPUMS International and IPUMS Terra, administrative units may be regionalized for confidentiality purposes. Units that have populations smaller than a designated threshold, usually 20,000 people, are combined with neighboring unit(s) to create a regionalized unit that is above the population threshold.

3IPUMS DHS also provides contextual variables summarizing characteristics of a 5-10 kilometer radius around each respondent's sample cluster and linking codes enabling users to attach contextual variables constructed from IPUMS International at the second administrative level. The DHS data themselves are not representative at these finer scales.

4 Many IPUMS PMA samples cover only selected portions of the country. A few samples include second administrative level detail.