The 2020 Census Production Settings Demographic and Housing Characteristics (DHC) Approximate Monte Carlo (AMC) method seed Privacy Protected Microdata File (PPMF0) and PPMF replicates (PPMF1, PPMF2, ..., PPMF50) are a set of microdata files intended for use in estimating the magnitude of error(s) introduced by the 2020 Census Disclosure Avoidance System (DAS) into the 2020 Census Redistricting Data Summary File (P.L. 94-171), the Demographic and Housing Characteristics File, and the Demographic Profile.

The PPMF0 was the source of the publicly released, official 2020 Census data products referenced above, and was created by executing the 2020 DAS TopDown Algorithm (TDA) using the confidential 2020 Census Edited File (CEF) as the initial input; the official location for the PPMF0 is on the United States Census Bureau FTP server, but we also include a copy of it here for convenience. The replicates were then created by executing the 2020 DAS TDA repeatedly with the PPMF0 as its initial input.

Inspired by analogy to the use of bootstrap methods in non-private contexts, U.S. Census Bureau (USCB) researchers explored whether simple calculations based on comparing each PPMFi to the PPMF0 could be used to reliably estimate the scale of errors introduced by the 2020 DAS, and generally found this approach worked well.

The PPMF0 and PPMFi files contained here are provided so that external researchers can estimate properties of DAS-introduced error without privileged access to internal USCB-curated data sets; further information on the estimation methodology can be found in Ashmead et. al 2024.

The 2020 DHC AMC seed PPMF0 and PPMF replicates have been cleared for public dissemination by the USCB Disclosure Review Board (CBDRB-FY22-DSEP-004). The PPMF0 and PPMF replicates contain all Person and Units attributes necessary to produce the 2020 Census Redistricting Data Summary File (P.L. 94-171), the Demographic and Housing Characteristics File, and the Demographic Profile for both the United States and Puerto Rico, and include geographic detail down to the Census Block level. They do not include attributes specific to either the Detailed DHC-A or Detailed DHC-B products; in particular, data on Major Race (e.g., White Alone) is included, but data on Detailed Race (e.g., Cambodian) is not included in the PPMF0 and replicates.

Census 2020 blocks in King County with selected P.L. 94-171 redistricting data.For more information about the P.L. 94-171 redistricting data, please visit the U.S. Census Bureau. For a detailed description of the data included please see the 2020 Census State Redistricting Data Summary File. Important note: The Census Bureau advises analysts to aggregate blocks together to form larger geographic units before using the 2020 Census data. Background: The Bureau used a new tool, called Differential Privacy, to inject statistical noise into the 2020 Census data in order to protect privacy. The resulting noise can cause substantial inaccuracy at the block level; combining data for blocks and other small geographies reduces the inaccuracy. For more information see Redistricting Data: What to Expect and When (census.gov), 2020 Census Data Products: Disclosure Avoidance Modernization.

The 2020 Census Demographic and Housing Characteristics Noisy Measurement File is an intermediate output of the 2020 Census Disclosure Avoidance System (DAS) TopDown Algorithm (TDA) (as described in Abowd, J. et al [2022], and implemented in primitives.py). The 2020 Census Demographic and Housing Characteristics Noisy Measurement File includes zero-Concentrated Differentially Private (zCDP) (Bun, M. and Steinke, T [2016]) noisy measurements, implemented via the discrete Gaussian mechanism (Cannone C., et al., [2023] ), which added positive or negative integer-valued noise to each of the resulting counts. These are estimated counts of individuals and housing units included in the 2020 Census Edited File (CEF), which includes confidential data collected in the 2020 Census of Population and Housing.

The noisy measurements included in this file were subsequently post-processed by the TopDown Algorithm (TDA) to produce the Census Demographic and Housing Characteristics Summary File. In addition to the noisy measurements, constraints based on invariant calculations --- counts computed without noise --- are also included (with the exception of the state-level total populations, which can be sourced separately from data.census.gov).

The Noisy Measurement File was produced using the official “production settings,” the final set of algorithmic parameters and privacy-loss budget allocations that were used to produce the 2020 Census Redistricting Data (P.L. 94-171) Summary File and the 2020 Census Demographic and Housing Characteristics File.

The noisy measurements are produced in an early stage of the TDA. Afterward, these noisy measurements are post-processed to ensure internal and hierarchical consistency within the resulting tables. The Census Bureau has released these noisy measurements to enable data users to evaluate the impact of disclosure avoidance variability on 2020 Census data. The 2020 Census Demographic and Housing Characteristics (DHC) Noisy Measurement File has been cleared for public dissemination by the Census Bureau Disclosure Review Board (CBDRB-FY22-DSEP-004).

The 2010 Census Production Settings Redistricting Data (P.L. 94-171) Demonstration Noisy Measurement Files are an intermediate output of the 2020 Census Disclosure Avoidance System (DAS) TopDown Algorithm (TDA) (as described in Abowd, J. et al [2022], and implemented in https://github.com/uscensusbureau/DAS_2020_Redistricting_Production_Code). The NMF was produced using the official "production settings," the final set of algorithmic parameters and privacy-loss budget allocations that were used to produce the 2020 Census Redistricting Data (P.L. 94-171) Summary File and the 2020 Census Demographic and Housing Characteristics File. The NMF consists of the full set of privacy-protected statistical queries (counts of individuals or housing units with particular combinations of characteristics) of confidential 2010 Census data relating to the redistricting data portion of the 2010 Demonstration Data Products Suite - Redistricting and Demographic and Housing Characteristics File - Production Settings (2023-04-03). These statistical queries, called "noisy measurements" were produced under the zero-Concentrated Differential Privacy framework (Bun, M. and Steinke, T [2016]; see also Dwork C. and Roth, A. [2014]) implemented via the discrete Gaussian mechanism (Cannone C., et al., [2023]), which added positive or negative integer-valued noise to each of the resulting counts. The noisy measurements are an intermediate stage of the TDA prior to the post-processing the TDA then performs to ensure internal and hierarchical consistency within the resulting tables. The Census Bureau has released these 2010 Census demonstration data to enable data users to evaluate the expected impact of disclosure avoidance variability on 2020 Census data. The 2010 Census Production Settings Redistricting Data (P.L. 94-171) Demonstration Noisy Measurement Files (2023-04-03) have been cleared for public dissemination by the Census Bureau Disclosure Review Board (CBDRB-FY22-DSEP-004). The data include zero-Concentrated Differentially Private (zCDP) (Bun, M. and Steinke, T [2016]) noisy measurements, implemented via the discrete Gaussian mechanism. These are estimated counts of individuals and housing units included in the 2010 Census Edited File (CEF), which includes confidential data initially collected in the 2010 Census of Population and Housing. The noisy measurements included in this file were subsequently post-processed by the TopDown Algorithm (TDA) to produce the 2010 Census Production Settings Privacy-Protected Microdata File - Redistricting (P.L. 94-171) and Demographic and Housing Characteristics File (2023-04-03) (https://www2.census.gov/programs-surveys/decennial/2020/program-management/data-product- planning/2010-demonstration-data-products/04 Demonstration_Data_Products_Suite/2023-04-03/). As these 2010 Census demonstration data are intended to support study of the design and expected impacts of the 2020 Disclosure Avoidance System, the 2010 CEF records were pre-processed before application of the zCDP framework. This pre-processing converted the 2010 CEF records into the input-file format, response codes, and tabulation categories used for the 2020 Census, which differ in substantive ways from the format, response codes, and tabulation categories originally used for the 2010 Census. The NMF provides estimates of counts of persons in the CEF by various characteristics and combinations of characteristics, including their reported race and ethnicity, whether they were of voting age, whether they resided in a housing unit or one of 7 group quarters types, and their census block of residence, after the addition of discrete Gaussian noise (with the scale parameter determined by the privacy-loss budget allocation for that particular query under zCDP). Noisy measurements of the counts of occupied and vacant housing units by census block are also included. Lastly, data on constraints--information into which no noise was infused by the Disclosure Avoidance System (DAS) and used by the TDA to post-process the noisy measurements into the 2010 Census Production Settings Privacy-Protected Microdata File - Redistricting (P.L. 94-171) and Demographic and Housing Characteristics File (2023-04-03) --are provided. These data are available for download (i.e. not restricted access). Due to their size, they must be downloaded through the link on this

[Metadata] 2020 Census Tract Boundaries, with population, for the State of Hawaii, excluding northwest Hawaiian Islands and clipped to the coastline. Source: US Census Bureau, September 2021. Added tract name, county and island fields, April 2022. Note: The Hawaii Statewide GIS Program was notified in Feb 2023 that the tract names for the Kalawao and Sprecklesville census tracts were reversed (both tracts have census tract number 319). The GIS staff corrected the error and re-published the layer, March 2, 2023. For additional information about this layer, please refer to metadata at https://files.hawaii.gov/dbedt/op/gis/data/tracts20.pdf or contact Hawaii Statewide GIS Program, Office of Planning and Sustainable Development, State of Hawaii; PO Box 2359, Honolulu, Hi. 96804; (808) 587-2846; email: gis@hawaii.gov; Website: https://planning.hawaii.gov/gis.

The 2010 Census Production Settings Demographic and Housing Characteristics Demonstration Noisy Measurement File (2023-04-03) is an intermediate output of the 2020 Census Disclosure Avoidance System (DAS) TopDown Algorithm (TDA) (as described in Abowd, J. et al [2022], and implemented in DAS 2020 Redistricting Production Code). The NMF was produced using the official "production settings," the final set of algorithmic parameters and privacy-loss budget allocations, that were used to produce the 2020 Census Redistricting Data (P.L. 94-171) Summary File and the 2020 Census Demographic and Housing Characteristics File. The NMF consists of the full set of privacy-protected statistical queries (counts of individuals or housing units with particular combinations of characteristics) of confidential 2010 Census data relating to the 2010 Demonstration Data Products Suite - Redistricting and Demographic and Housing Characteristics File - Production Settings (2023-04-03). These statistical queries, called "noisy measurements" were produced under the zero-Concentrated Differential Privacy framework (Bun, M. and Steinke, T [2016]; see also Dwork C. and Roth, A. [2014]) implemented via the discrete Gaussian mechanism (Cannone C., et al., [2023]), which added positive or negative integer-valued noise to each of the resulting counts. The noisy measurements are an intermediate stage of the TDA prior to the post-processing the TDA then performs to ensure internal and hierarchical consistency within the resulting tables. The Census Bureau has released these 2010 Census demonstration data to enable data users to evaluate the expected impact of disclosure avoidance variability on 2020 Census data. The 2010 Census Production Settings Demographic and Housing Characteristics (DHC) Demonstration Noisy Measurement File (2023-04-03) has been cleared for public dissemination by the Census Bureau Disclosure Review Board (CBDRB-FY22-DSEP-004). The 2010 Census Production Settings Demographic and Housing Characteristics Demonstration Noisy Measurement File (2023-04-03) includes zero-Concentrated Differentially Private (zCDP) (Bun, M. and Steinke, T [2016]) noisy measurements, implemented via the discrete Gaussian mechanism. These are estimated counts of individuals and housing units included in the 2010 Census Edited File (CEF), which includes confidential data initially collected in the 2010 Census of Population and Housing. The noisy measurements included in this file were subsequently post-processed by the TopDown Algorithm (TDA) to produce the 2010 Census Production Settings Privacy-Protected Microdata File - Redistricting (P.L. 94-171) and Demographic and Housing Characteristics File (2023-04-03) (Demonstration Data Products Suite/2023-04-03/). As these 2010 Census demonstration data are intended to support study of the design and expected impacts of the 2020 Disclosure Avoidance System, the 2010 CEF records were pre-processed before application of the zCDP framework. This pre-processing converted the 2010 CEF records into the input-file format, response codes, and tabulation categories used for the 2020 Census, which differ in substantive ways from the format, response codes, and tabulation categories originally used for the 2010 Census. The NMF provides estimates of counts of persons in the CEF by various characteristics and combinations of characteristics including their reported race and ethnicity, whether they were of voting age, whether they resided in a housing unit or one of 7 group quarters types, and their census block of residence after the addition of discrete Gaussian noise (with the scale parameter determined by the privacy-loss budget allocation for that particular query under zCDP). Noisy measurements of the counts of occupied and vacant housing units by census block are also included. Lastly, data on constraints--information into which no noise was infused by the Disclosure Avoidance System (DAS) and used by the TDA to post-process the noisy measurements into the 2010 Census Production Settings Privacy-Protected Microdata File - Redistricting (P.L. 94-171) and Demographic and Housing Characteristics File (2023-04-03) --are provided. These data are available for download (i.e. not restricted access). Due to their size, they must be downloaded through the link on this metadata page and not through the standard ICPSR downloa

Note: For information on data collection, confidentiality protection, nonsampling error, subject definitions, and guidance on using the data, access the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..To protect respondent confidentiality, data have undergone disclosure avoidance methods which add statistical "noise" - small, random additions or subtractions - to the data so that no one can reliably link the published data to a specific person or household. As a result, data users may observe implausible and improbable data within this product and compared with other 2020 Census data products. For more information, access the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..The degree of uncertainty introduced by statistical noise and post-processing is represented through a 90 percent credible interval (CI). The CI does not account for the truncation of large households (maximum of 10 persons per household or 6 children under 18 years). The CI can be interpreted as providing 90 percent probability that the truncated value is between the lower and upper end points. The enumerated value can be larger than the 90% CI high value given household truncation. For information on the impact of truncation, refer to the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..Source: U.S. Census Bureau, 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC)

Note: For information on data collection, confidentiality protection, nonsampling error, subject definitions, and guidance on using the data, access the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..To protect respondent confidentiality, data have undergone disclosure avoidance methods which add statistical "noise" - small, random additions or subtractions - to the data so that no one can reliably link the published data to a specific person or household. As a result, data users may observe implausible and improbable data within this product and compared with other 2020 Census data products. For more information, access the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..The degree of uncertainty introduced by statistical noise and post-processing is represented through a 90 percent credible interval (CI). The CI does not account for the truncation of large households (maximum of 10 persons per household or 6 children under 18 years). The CI can be interpreted as providing 90 percent probability that the truncated value is between the lower and upper end points. The enumerated value can be larger than the 90% CI high value given household truncation. For information on the impact of truncation, refer to the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation.."Families" consist of a householder and one or more other people related to the householder by birth, marriage, or adoption..Source: U.S. Census Bureau, 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC)

[Metadata] 2020 Census Block Group Boundaries, with population, for the State of Hawaii, excluding northwest Hawaiian Islands and clipped to the coastline. Source: US Census Bureau, September 2021. For additional information about this layer, please refer to metadata at https://files.hawaii.gov/dbedt/op/gis/data/blkgrp20.pdf or contact Hawaii Statewide GIS Program, Office of Planning and Sustainable Development, State of Hawaii; PO Box 2359, Honolulu, Hi. 96804; (808) 587-2846; email: gis@hawaii.gov; Website: https://planning.hawaii.gov/gis.

The TIGER/Line Files are shapefiles and related database files (.dbf) that are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line File is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Census tracts are small, relatively permanent statistical subdivisions of a county or equivalent entity, and were defined by local participants as part of the 2020 Census Participant Statistical Areas Program. The Census Bureau delineated the census tracts in situations where no local participant existed or where all the potential participants declined to participate. The primary purpose of census tracts is to provide a stable set of geographic units for the presentation of census data and comparison back to previous decennial censuses. Census tracts generally have a population size between 1,200 and 8,000 people, with an optimum size of 4,000 people. When first delineated, census tracts were designed to be homogeneous with respect to population characteristics, economic status, and living conditions. The spatial size of census tracts varies widely depending on the density of settlement. Physical changes in street patterns caused by highway construction, new development, and so forth, may require boundary revisions. In addition, census tracts occasionally are split due to population growth, or combined as a result of substantial population decline. Census tract boundaries generally follow visible and identifiable features. They may follow legal boundaries such as minor civil division (MCD) or incorporated place boundaries in some States and situations to allow for census tract-to-governmental unit relationships where the governmental boundaries tend to remain unchanged between censuses. State and county boundaries always are census tract boundaries in the standard census geographic hierarchy. In a few rare instances, a census tract may consist of noncontiguous areas. These noncontiguous areas may occur where the census tracts are coextensive with all or parts of legal entities that are themselves noncontiguous. For the 2020 Census, the census tract code range of 9400 through 9499 was enforced for census tracts that include a majority American Indian population according to Census 2000 data and/or their area was primarily covered by federally recognized American Indian reservations and/or off-reservation trust lands; the code range 9800 through 9899 was enforced for those census tracts that contained little or no population and represented a relatively large special land use area such as a National Park, military installation, or a business/industrial park; and the code range 9900 through 9998 was enforced for those census tracts that contained only water area, no land area.

Note: For information on data collection, confidentiality protection, nonsampling error, subject definitions, and guidance on using the data, access the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..To protect respondent confidentiality, data have undergone disclosure avoidance methods which add statistical "noise" - small, random additions or subtractions - to the data so that no one can reliably link the published data to a specific person or household. As a result, data users may observe implausible and improbable data within this product and compared with other 2020 Census data products. For more information, access the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..The degree of uncertainty introduced by statistical noise and post-processing is represented through a 90 percent credible interval (CI). The CI does not account for the truncation of large households (maximum of 10 persons per household or 6 children under 18 years). The CI can be interpreted as providing 90 percent probability that the truncated value is between the lower and upper end points. The enumerated value can be larger than the 90% CI high value given household truncation. For information on the impact of truncation, refer to the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation.."Families" consist of a householder and one or more other people related to the householder by birth, marriage, or adoption..Source: U.S. Census Bureau, 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC)

Note: For information on data collection, confidentiality protection, nonsampling error, subject definitions, and guidance on using the data, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..The Hispanic origin and race codes were updated in 2020. For more information on the Hispanic origin and race code changes, access Improvements to the 2020 Census Race and Hispanic Origin Question Designs, Data Processing, and Coding Procedures..To protect respondent confidentiality, data have undergone disclosure avoidance methods which add "statistical noise" - small, random additions or subtractions - to the data so that no one can reliably link the published data to a specific person or household. As a result, data users may observe implausible and improbable data within this data product and compared with other 2020 Census data products. For more information, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Aggregating data, such as household counts and geographies, diminishes accuracy and increases the likelihood of inconsistent and improbable results. For guidance on creating custom aggregations, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Counts showing an "X" are suppressed for one of two reasons: (1) the count was negative or (2) it is an alone count larger than its equivalent alone or in any combination count. If the suppressed count is an alone count, data users should use the equivalent alone in any combination count, if it is available..This racial or ethnic group has data available for three tenure categories. For more information on the minimum population counts and accuracy, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Washington, D.C. and American Indian/Alaska Native/Native Hawaiian (AIANNH) areas may show data when there should not be any displayed. This is due to postprocessing to ensure counts for statistically equivalent and coterminous geographies are consistent. For more information, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Source: U.S. Census Bureau, 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B)

The TIGER/Line Files are shapefiles and related database files (.dbf) that are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line File is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. American Indian tribal subdivisions are administrative subdivisions of federally recognized American Indian reservations / off-reservation trust lands or Oklahoma tribal statistical areas (OTSAs). These entities are internal units of self-government and/or administration that serve social, cultural, and/or economic purposes for the American Indian Tribe or Tribes on the reservations / off-reservation trust lands or OTSAs. The Census Bureau obtains the boundary and attribute information for tribal subdivisions on federally recognized American Indian reservations and off-reservation trust lands from federally recognized tribal governments through the Census Bureau's Boundary and Annexation Survey (BAS). For the 2020 Census, the boundaries for tribal subdivisions on OTSAs were also obtained from federally recognized tribal governments through the Tribal Statistical Areas Program (TSAP). Note that tribal subdivisions do not exist on all reservations / off-reservation trust lands or OTSAs, rather only where they were submitted to the Census Bureau by the federally recognized tribal government for that area.

Note: For information on data collection, confidentiality protection, nonsampling error, subject definitions, and guidance on using the data, access the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..To protect respondent confidentiality, data have undergone disclosure avoidance methods which add statistical "noise" - small, random additions or subtractions - to the data so that no one can reliably link the published data to a specific person or household. As a result, data users may observe implausible and improbable data within this product and compared with other 2020 Census data products. For more information, access the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation..The degree of uncertainty introduced by statistical noise and post-processing is represented through a 90 percent credible interval (CI). The CI does not account for the truncation of large households (maximum of 10 persons per household or 6 children under 18 years). The CI can be interpreted as providing 90 percent probability that the truncated value is between the lower and upper end points. The enumerated value can be larger than the 90% CI high value given household truncation. For information on the impact of truncation, refer to the 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC) Technical Documentation.."Spouse" and "unmarried partner" represent spouse or unmarried partner of the householder. It does not reflect all spouses or unmarried partners in a household.."Nonrelative" represents household members not related to the householder by birth, marriage, or adoption.."Own child" includes biological, adopted, and stepchildren of the householder..Source: U.S. Census Bureau, 2020 Census Supplemental Demographic and Housing Characteristics File (S-DHC)

[Metadata] 2020 Census County Division Boundaries (aka Districts), with population, for the State of Hawaii, excluding northwest Hawaiian Islands and clipped to the coastline. Source: US Census Bureau, September 2021. For additional information about this layer, please refer to metadata at https://files.hawaii.gov/dbedt/op/gis/data/ccd20.pdf or contact Hawaii Statewide GIS Program, Office of Planning and Sustainable Development, State of Hawaii; PO Box 2359, Honolulu, Hi. 96804; (808) 587-2846; email: gis@hawaii.gov; Website: https://planning.hawaii.gov/gis.

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. The primary legal divisions of most states are termed counties. In Louisiana, these divisions are known as parishes. In Alaska, which has no counties, the equivalent entities are the organized boroughs, city and boroughs, municipalities, and for the unorganized area, census areas. The latter are delineated cooperatively for statistical purposes by the State of Alaska and the Census Bureau. In four states (Maryland, Missouri, Nevada, and Virginia), there are one or more incorporated places that are independent of any county organization and thus constitute primary divisions of their states. These incorporated places are known as independent cities and are treated as equivalent entities for purposes of data presentation. The District of Columbia and Guam have no primary divisions, and each area is considered an equivalent entity for purposes of data presentation. The Census Bureau treats the following entities as equivalents of counties for purposes of data presentation: Municipios in Puerto Rico, Districts and Islands in American Samoa, Municipalities in the Commonwealth of the Northern Mariana Islands, and Islands in the U.S. Virgin Islands. The entire area of the United States, Puerto Rico, and the Island Areas is covered by counties or equivalent entities. The boundaries for counties and equivalent entities are as of January 1, 2018, primarily as reported through the Census Bureau's Boundary and Annexation Survey (BAS).

Note: For information on data collection, confidentiality protection, nonsampling error, subject definitions, and guidance on using the data, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..The Hispanic origin and race codes were updated in 2020. For more information on the Hispanic origin and race code changes, access Improvements to the 2020 Census Race and Hispanic Origin Question Designs, Data Processing, and Coding Procedures..To protect respondent confidentiality, data have undergone disclosure avoidance methods which add "statistical noise" - small, random additions or subtractions - to the data so that no one can reliably link the published data to a specific person or household. As a result, data users may observe implausible and improbable data within this data product and compared with other 2020 Census data products. For more information, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Aggregating data, such as household counts and geographies, diminishes accuracy and increases the likelihood of inconsistent and improbable results. For guidance on creating custom aggregations, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Counts showing an "X" are suppressed for one of two reasons: (1) the count was negative or (2) it is an alone count larger than its equivalent alone or in any combination count. If the suppressed count is an alone count, data users should use the equivalent alone in any combination count, if it is available..This racial or ethnic group has data available for two household type categories. More detailed household type data are not available due to minimum population counts not being met. For more information on the minimum population counts and accuracy, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Washington, D.C. and American Indian/Alaska Native/Native Hawaiian (AIANNH) areas may show data when there should not be any displayed. This is due to postprocessing to ensure counts for statistically equivalent and coterminous geographies are consistent. For more information, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Source: U.S. Census Bureau, 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B)

US Census 2020 File03 (Table P5), Subjects Group Quarters Population by Major Group Quarters Type. A unique logical record number (LOGRECNO in the geographic header) is assigned to all files for a specific geographic entity. This field is the key that links records across all four files. Besides the logical record number, other identifying fields also are carried over from the geographic header file to the table files. These are file identification (FILEID), state/U.S. abbreviation (STUSAB), characteristic iteration (CHARITER), and characteristic iteration file sequence number (CIFSN). The geographic header is standard across all electronic data products from the 2020 Census. Note that some fields in the Redistricting products are not filled. For example, the CHARITER field is used in other 2020 Census products; in the 2020 Census State Redistricting Data (Public Law 94-171) Summary File, it is always coded as 000, GEOIDs are related to Census Tracts. For table P5 details refer to the online census documentation: 2020 Census State Redistricting Data (Public Law 94-171) Summary File

[Metadata] 2020 Census Urban Areas for the State of Hawaii. Source: US Census Bureau, 2023. 2020 Census Urban Areas consist of 5,000 or more people or 2,000 or more housing units. For additional information, please refer to metadata at https://files.hawaii.gov/dbedt/op/gis/data/uac20.pdf or contact Hawaii Statewide GIS Program, Office of Planning and Sustainable Development, State of Hawaii; PO Box 2359, Honolulu, Hi. 96804; (808) 587-2846; email: gis@hawaii.gov; Website: https://planning.hawaii.gov/gis.

Note: For information on data collection, confidentiality protection, nonsampling error, subject definitions, and guidance on using the data, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..The Hispanic origin and race codes were updated in 2020. For more information on the Hispanic origin and race code changes, access Improvements to the 2020 Census Race and Hispanic Origin Question Designs, Data Processing, and Coding Procedures..To protect respondent confidentiality, data have undergone disclosure avoidance methods which add "statistical noise" - small, random additions or subtractions - to the data so that no one can reliably link the published data to a specific person or household. As a result, data users may observe implausible and improbable data within this data product and compared with other 2020 Census data products. For more information, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Aggregating data, such as household counts and geographies, diminishes accuracy and increases the likelihood of inconsistent and improbable results. For guidance on creating custom aggregations, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Counts showing an "X" are suppressed for one of two reasons: (1) the count was negative or (2) it is an alone count larger than its equivalent alone or in any combination count. If the suppressed count is an alone count, data users should use the equivalent alone in any combination count, if it is available..This racial or ethnic group has data available for eight household type categories. For more information on the minimum population counts and accuracy, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Washington, D.C. and American Indian/Alaska Native/Native Hawaiian (AIANNH) areas may show data when there should not be any displayed. This is due to postprocessing to ensure counts for statistically equivalent and coterminous geographies are consistent. For more information, access the 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B) Technical Documentation..Source: U.S. Census Bureau, 2020 Census Detailed Demographic and Housing Characteristics File B (Detailed DHC-B)