This data set represents 1990 population density by block group as a 100-m grid using data from the 1990 Census of Population and Housing (Public Law 94-171 redistricting data). Grid cell values represent population density in people per square kilometer multiplied by 10 so that the data could be stored as integer.

Grid of population density in the conterminous United States at a resolution of one kilometer. The grid was converted from an ASCII file obtained from the Consortium for International Earth Science Information Network (CIESIN).

These data show the total population, total housing units, and median household income from the 2010 to 2016 U.S. Census Bureau American Community Survey. These values have been merged with the 2010 Decennial Census boundaries at the state level. Also included are records for the District of Columbia, Puerto Rico, American Samoa, the Commonwealth of the Northern Mariana Islands, Guam, and the U.S. Virgin Islands.

Annual Housing Unit Estimates for the United States, States, and Counties: April 1, 2010 to July 1, 2019 // Source: U.S. Census Bureau, Population Division // Note: The estimates are based on the 2010 Census and reflect changes to the April 1, 2010 housing units due to the Count Question Resolution program and geographic program revisions // Each year, the Census Bureau's Population and Housing Unit Estimates Program utilizes current data on new residential construction, placements of manufactured housing, and housing unit loss to calculate change in the housing stock since the most recent decennial census, and produces a time series of housing unit estimates. The annual time series of estimates begins with the most recent decennial census data and extends to the vintage year. The vintage year (e.g., V2019) refers to the final year of the time series. The reference date for all estimates is July 1, unless otherwise specified. With each new issue of estimates, the entire estimates series is revised. Additional information, including historical and intercensal estimates, evaluation estimates, demographic analysis, research papers, and methodology is available on website: https://www.census.gov/programs-surveys/popest.html.

This dataset represents the population and housing unit density within individual local and accumulated upstream catchments for NHDPlusV2 Waterbodies based on the 2010 US Census data (See Supplementary Info for Glossary of Terms). Densities are calculated for every block group and watershed averages are calculated for every local NHDPlusV2 catchment. Catchment boundaries in LakeCat are defined in one of two ways, on-network or off-network. The on-network catchment boundaries follow the catchments provided in the NHDPlusV2 and the metrics for these lakes mirror metrics from StreamCat, but will substitute the COMID of the NHDWaterbody for that of the NHDFlowline. The off-network catchment framework uses the NHDPlusV2 flow direction rasters to define non-overlapping lake-catchment boundaries and then links them through an off-network flow table. This data set is derived from The TIGER/Line Files and related database (.dbf) files for the conterminous USA. It was downloaded as Block Group-Level Census 2010 SF1 Data in File Geodatabase Format (ArcGIS version 10.0). The landscape raster (LR) was produced based on the data compiled from the questions asked of all people and about every housing unit. The (block-group population / block group area) and (block-group housing units / block group area) were summarized by local catchment and by watershed to produce local catchment-level and watershed-level metrics as a continuous data type.

U.S. Census Tracts represents the U.S. Census tracts of the United States in the 50 states, the District of Columbia, and Puerto Rico.

Intercensal Estimates of the Resident Population by Age Groups, Race by Sex, and Hispanic Origin for Counties: July 1, 1990 to July 1, 1999 // Source: U.S. Census Bureau, Population Division // For detailed information about the methods used to create the intercensal population estimates, see https://www.census.gov/popest/methodology/intercensal_nat_meth.pdf. // The Census Bureau's Population Estimates Program produces intercensal estimates each decade by adjusting the existing time series of postcensal estimates for a decade to smooth the transition from one decennial census count to the next. They differ from the postcensal estimates that are released annually because they rely on a formula that redistributes the difference between the April 1 postcensal estimate and April 1 census count for the end of the decade across the estimates for that decade. Meanwhile, the postcensal estimates incorporate current data on births, deaths, and migration to produce each new vintage of estimates, and to revise estimates for years back to the last census. The Population Estimates Program provides additional information including historical and postcensal estimates, evaluation estimates, demographic analysis, and research papers on its website: https://www.census.gov/popest/index.html.

The data reflects Maryland's Intercensal Estimates of total residential population from both decennial and non-decennial counts. The total residential populations from 1790 to 1890 are based on the decennial census data, utilizing sources from the IPUMs National Historical Geographic Information System (NHGIS). For the years 1900 to 2020, both decennial and non-decennial population counts were produced by the Population Distribution Branch of the U.S. Census Bureau. Intercensal estimates are generated every 10 years following the decennial census, with estimates from previous decades being revised to align with the most current census data.