Abstract

A crosswalk dataset matching US ZIP codes to corresponding census tracts

Documentation

The denominators used to calculate the address ratios are the ZIP code totals. When a ZIP is split by any of the other geographies, that ZIP code is duplicated in the crosswalk file.

**Example: **ZIP code 03870 is split by two different Census tracts, 33015066000 and 33015071000, which appear in the tract column. The ratio of residential addresses in the first ZIP-Tract record to the total number of residential addresses in the ZIP code is .0042 (.42%). The remaining residential addresses in that ZIP (99.58%) fall into the second ZIP-Tract record.

So, for example, if one wanted to allocate data from ZIP code 03870 to each Census tract located in that ZIP code, one would multiply the number of observations in the ZIP code by the residential ratio for each tract associated with that ZIP code.

https://redivis.com/fileUploads/4ecb405e-f533-4a5b-8286-11e56bb93368%3E" alt="">(Note that the sum of each ratio column for each distinct ZIP code may not always equal 1.00 (or 100%) due to rounding issues.)

Census tract definition

A census tract, census area, census district or meshblock is a geographic region defined for the purpose of taking a census. Sometimes these coincide with the limits of cities, towns or other administrative areas and several tracts commonly exist within a county. In unincorporated areas of the United States these are often arbitrary, except for coinciding with political lines.

Further reading

The following article demonstrates how to more effectively use the U.S. Department of Housing and Urban Development (HUD) United States Postal Service ZIP Code Crosswalk Files when working with disparate geographies.

Wilson, Ron and Din, Alexander, 2018. “Understanding and Enhancing the U.S. Department of Housing and Urban Development’s ZIP Code Crosswalk Files,” Cityscape: A Journal of Policy Development and Research, Volume 20 Number 2, 277 – 294. URL: https://www.huduser.gov/portal/periodicals/cityscpe/vol20num2/ch16.pdf

Contact information

Questions regarding these crosswalk files can be directed to Alex Din with the subject line HUD-Crosswalks.

Acknowledgement

This dataset is taken from the U.S. Department of Housing and Urban Development (HUD) office: https://www.huduser.gov/portal/datasets/usps_crosswalk.html#codebook

Crosswalk between Census tracts (2010) and Arizona Dept. of Health Services Primary Care Areas (PCAs). This version is used to identify PCAs by tract for Census 2010 data. If you're working with American Community Survey (ACS) data, use this version instead.Why did ADHS develop two Tract to PCA conversion keys?The U.S. Census Bureau changed the tract ID for seven tracts in American Community Survey (ACS) data from the originally assigned tract id in the 2010 Census data release. As a result, two crosswalks are needed, one for Census 2010 and another for ACS data. Use the correct one depending on the source of your data.

Because the 2020 Census relationship files released by the Census Bureau did not include population or housing unit percentage allocations, alternative methodologies to allocate population and housing units between 2010 and 2020 Census tracts were tested. The methodology selected by DRU was to use building footprints and residential parcels at the 2020 Census block level to allocate population and housing units.

Abstract

A crosswalk matching US ZIP codes to corresponding CBSA (core-based statistical area)

Documentation

The denominators used to calculate the address ratios are the ZIP code totals. When a ZIP is split by any of the other geographies, that ZIP code is duplicated in the crosswalk file.

**Example: **ZIP code 03870 is split by two different Census tracts, 33015066000 and 33015071000, which appear in the tract column. The ratio of residential addresses in the first ZIP-Tract record to the total number of residential addresses in the ZIP code is .0042 (.42%). The remaining residential addresses in that ZIP (99.58%) fall into the second ZIP-Tract record.

So, for example, if one wanted to allocate data from ZIP code 03870 to each Census tract located in that ZIP code, one would multiply the number of observations in the ZIP code by the residential ratio for each tract associated with that ZIP code.

https://redivis.com/fileUploads/4ecb405e-f533-4a5b-8286-11e56bb93368%3E" alt="">(Note that the sum of each ratio column for each distinct ZIP code may not always equal 1.00 (or 100%) due to rounding issues.)

CBSA definition

A core-based statistical area (CBSA) is a U.S. geographic area defined by the Office of Management and Budget (OMB) that consists of one or more counties (or equivalents) anchored by an urban center of at least 10,000 people plus adjacent counties that are socioeconomically tied to the urban center by commuting. Areas defined on the basis of these standards applied to Census 2000 data were announced by OMB in June 2003. These standards are used to replace the definitions of metropolitan areas that were defined in 1990. The OMB released new standards based on the 2010 Census on July 15, 2015.

Further reading

The following article demonstrates how to more effectively use the U.S. Department of Housing and Urban Development (HUD) United States Postal Service ZIP Code Crosswalk Files when working with disparate geographies.

Wilson, Ron and Din, Alexander, 2018. “Understanding and Enhancing the U.S. Department of Housing and Urban Development’s ZIP Code Crosswalk Files,” Cityscape: A Journal of Policy Development and Research, Volume 20 Number 2, 277 – 294. URL: https://www.huduser.gov/portal/periodicals/cityscpe/vol20num2/ch16.pdf

Contact authors

Questions regarding these crosswalk files can be directed to Alex Din with the subject line HUD-Crosswalks.

Acknowledgement

This dataset is taken from the U.S. Department of Housing and Urban Development (HUD) office: https://www.huduser.gov/portal/datasets/usps_crosswalk.html#codebook

The Postal Code Conversion File (PCCF) is a digital file which provides a correspondence between the Canada Post Corporation (CPC) six-character postal code and Statistics Canada's standard geographic areas for which census data and other statistics are produced. Through the link between postal codes and standard geographic areas, the PCCF permits the integration of data from various sources. The Single Link Indicator provides one best link for every postal code, as there are multiple records for many postal codes. The geographic coordinates attached to each postal code on the PCCF are commonly used to map the distribution of data for spatial analysis (e.g., clients, activities). The location information is a powerful tool for planning, or research purposes. In April 1983, the Geography Division released the first version of the Postal Code Conversion File, which linked postal codes to census geographic areas and included geographic coordinates. Since then, the file has been updated on a regular basis to reflect postal code changes provided by Canada Post Corporation. Every five years, the postal code linkages on the Postal Code Conversion File are “converted” to the latest census geographic areas. The original Postal Code Conversion File was linked to the 1981 Census geographic areas. Since then, the Postal Code Conversion File has undergone four “conversions”, following the 1986, 1991 and 1996 censuses. An automated system was used for the 1991-1996 conversion. Also, for the first time, the 1996 Census reported postal codes were used to validate the PCCF links. To obtain the postal code conversion file or for questions, consult the DLI contact at your educational institution.

Crosswalk between Census tracts (2010) and Arizona Dept. of Health Services Primary Care Areas (PCAs). This version is used to identify PCAs by tract for American Community Survey (ACS) data. If you're working with Census 2010 data, use this version instead.Why did ADHS develop two Tract to PCA conversion keys?The U.S. Census Bureau changed the tract ID for seven tracts in American Community Survey (ACS) data from the originally assigned tract id in the 2010 Census data release. As a result, two crosswalks are needed, one for Census 2010 and another for ACS data. Use the correct one depending on the source of your data.

This API returns the US Census Block geography ID information given a passed Latitude and Longitude.

Usage note: please be aware … Statistics Canada confirmed on May 10th, 2018, that a number of particular postal codesOM are missing in the June 2017 (published in December 2017) release of the PCCF, but was not able provide specifics about why these are missing. However, Statistics Canada checked each missing postal code against the newest internal release of the product, and they did exist in that file. The postal codesOM in question should be available in the August 2018 file. The Postal Code Conversion File (PCCF) is a digital file which provides a correspondence between the Canada Post Corporation (CPC) six-character postal code and Statistics Canada's standard geographic areas for which census data and other statistics are produced. Through the link between postal codes and standard geographic areas, the PCCF permits the integration of data from various sources. The Single Link Indicator provides one best link for every postal code, as there are multiple records for many postal codes. To obtain the postal code conversion file or for questions, consult the DLI contact at your educational institution. The geographic coordinates attached to each postal code on the PCCF are commonly used to map the distribution of data for spatial analysis (e.g., clients, activities). The location information is a powerful tool for planning, or research purposes. The geographic coordinates, which represent the standard geostatistical areas linked to each postal codeOM on the PCCF, are commonly used to map the distribution of data for spatial analysis (e.g., clients, activities). The location information is a powerful tool for marketing, planning, or research purposes. In April 1983, the Statistical Registers and Geography Division released the first version of the PCCF, which linked postal codesOM to 1981 Census geographic areas and included geographic coordinates. Since then, the file has been updated on a regular basis to reflect changes. For this release of the PCCF, the vast majority of the postal codesOM are directly geocoded to 2016 Census geography while others are linked via various conversion processes. A quality indicator for the confidence of this linkage is available in the PCCF.

Displacement risk indicator showing the number of housing units subject to conversion into condominiums summarized at the census tract level; available for every year from 2004 through the most recent year of available data.

The Postal Code Conversion File (PCCF) is a digital file which provides a correspondence between the Canada Post Corporation (CPC) six-character postal code and Statistics Canada's standard geographic areas for which census data and other statistics are produced. Through the link between postal codes and standard geographic areas, the PCCF permits the integration of data from various sources. The Single Link Indicator provides one best link for every postal code, as there are multiple records for many postal codes. To obtain the postal code conversion file or for questions, consult the DLI contact at your educational institution. The geographic coordinates attached to each postal code on the PCCF are commonly used to map the distribution of data for spatial analysis (e.g., clients, activities). The location information is a powerful tool for planning, or research purposes. The geographic coordinates, which represent the standard geostatistical areas linked to each postal codeOM on the PCCF, are commonly used to map the distribution of data for spatial analysis (e.g., clients, activities). The location information is a powerful tool for marketing, planning, or research purposes. In April 1983, the Statistical Registers and Geography Division released the first version of the PCCF, which linked postal codesOM to 1981 Census geographic areas and included geographic coordinates. Since then, the file has been updated on a regular basis to reflect changes. For this release of the PCCF, the vast majority of the postal codesOM are directly geocoded to 2016 Census geography while others are linked via various conversion processes. A quality indicator for the confidence of this linkage is available in the PCCF.

Analysis of ‘Condo Conversions by Census Tract’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/c66c36ca-2bb3-4a14-bb99-a9daeec64b44 on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Displacement risk indicator showing the number of housing units subject to conversion into condominiums summarized at the census tract level; available for every year from 2004 through the most recent year of available data.

--- Original source retains full ownership of the source dataset ---

These files provide a way to convert U.S. Census Bureau data from one set of geographies to another -- for example, from census tracts to county subdivisions, or 2010-era census tracts to 2020-era census tracts.

Note on new file formats April 2018 The original files for this census were the Esri .e00 interchange format files and the Mapinfo format files. Shapefile and geojson format files suitable for use with newer technology were created using GDAL: http://www.gdal.org/ Specifically, files were converted from Mapinfo: ogr2ogr -f {fileformat} {mif or tab input file} {output file} Note that some lengthy field names may be truncated. If you wish to use the original files provided by Statistics Canada, please use either .e00 format or Mapinfo format.

Overview The PCCF+ is a SAS control program and set of associated datasets derived from the PCCF, a 2021 postal code population weight file, the Geographic Attribute File, Health Region boundary files, and other supplementary data. PCCF+ automatically assigns a range of Statistics Canada standard geographic areas and other geographic identifiers based on postal codes. PCCF+ differs from the PCCF in that it: Uses population-weighted random allocation for many postal codes that link to more than one geographic area. Options are available for institutional postal codes. Procedures are included to link partial postal codes to geographic identifiers where possible. Problem records and diagnostics are provided in the program output, along with reference information for possible solutions. The geographic coordinates, which represent the standard geostatistical areas linked to each postal code on the PCCF, are commonly used to map the distribution of data for spatial analysis (e.g., clients, activities). In April 1983, the Geography Division released the first version of the PCCF, which linked postal codes to 1981 census geographic areas and included geographic coordinates. PCCF+ was first created using the 1986 census and has been updated regularly with population weight files calculated for each census from 1991 through 2021. Purpose of PCCF+ The purpose of the PCCF+ is to provide a link between six-character postal codes produced by the Canada Post Corporation (CPC), standard 2021 Census geographic areas (such as dissemination areas, census subdivisions, and census tracts) produced by Statistics Canada, and supplementary administrative areas and neighbourhood income quintiles. Postal codes do not respect census geographic boundaries and so may be linked to more than one standard geographic area, or assigned to more than one set of coordinates. Therefore, one postal code may be represented by more than one record. The PCCF product, produced by Statistics Canada, provides links between postal codes and all recorded matches to census geography. PCCF+ uses the PCCF but provides additional functionality in that it uses a population-weighted matching process for some residential postal codes where more than one geographic code is possible. PCCF+ also provides routines for institutional postal codes and for historic postal codes. The PCCF+ Version 8B includes a population-weighting file calculated from the 2021 Census population counts Neighbourhood income quintiles and deciles have been calculated from 2021 Census population data. The routine that allowed geocoding of historical postal codes in British Columbia (V1H, V9G, prior 1998) has been removed.

The PCCF+ is a SAS© control program and set of associated datasets derived from the PCCF, a 2011 postal codeOM population weight file, the Geographic Attribute File, Health Region boundary files, and other supplementary data. PCCF+ automatically assigns a range of Statistics Canada standard geographic areas and other geographic identifiers based on postal codesOM. PCCF+ differs from the PCCF in that it: Uses population-weighted random allocation for many postal codesOM that link to more than one geographic area. Options are available for institutional postal codesOM. Procedures are included to link partial postal codesOM to geographic identifiers where possible. Problem records and diagnostics are provided in the program output, along with reference information for possible solutions. The geographic coordinates, which represent the standard geostatistical areas linked to each postal codesOM on the PCCF, are commonly used to map the distribution of data for spatial analysis (e.g., clients, activities). In April 1983, the Geography Division released the first version of the PCCF, which linked postal codes to 1981 census geographic areas and included geographic coordinates. PCCF+ was first created using the 1986 census and has been updated regularly with population weight files calculated for each census from 1991 through 2011. The purpose of the PCCF+ is to provide a link between six-character postal codesOM produced by the Canada Post Corporation (CPC), standard 2021 Census geographic areas (such as dissemination areas, census subdivisions, and census tracts) produced by Statistics Canada, and supplementary administrative areas and neighbourhood income quintiles. Postal codesOM do not respect census geographic boundaries and so may be linked to more than one standard geographic area, or assigned to more than one set of coordinates. Therefore, one postal codeOM may be represented by more than one record. The PCCF product, produced by Statistics Canada, provides links between postal codes and all recorded matches to census geography. PCCF+ uses the PCCF but provides additional functionality in that it uses a population-weighted matching process for some residential postal codesOM where more than one geographic code is possible. PCCF+ also provides routines for institutional postal codesOM and for historic postal codesOM. The purpose of this product is not to validate postal codesOM or the PCCF.

Canopy data was derived from NAIP imagery and aggregated to the tract boundaries. Population data was taken directly from the 2020 census. Canopy percentage values were calculated by dividing the canopy assessment values by land area not the total county area. Ecosystem service benefit estimates were calculated using conversion factors found in the sample report from I-Tree Canopy (https://canopy.itreetools.org/report)

The Postal Code Conversion File (PCCF) links six-character postal codes to standard geographic areas such as dissemination areas, census tracts, and census subdivisions. By linking postal codes to standard geographic areas, the file facilitates the extraction and subsequent aggregation of data for selected geographic areas. The PCCF also associates each postal code with a longitude and latitude coordinate to support mapping applications.

OverviewThese are the Homeless Counts for 2020 as provided by the Los Angeles Homeless Services Authority (LAHSA), and the cities of Glendale, Pasadena, and Long Beach. The majority of this data comes from LAHSA using tract-level counts; the cities of Glendale, Pasadena, and Long Beach did not have tract-level counts available. The purpose of this layer is to depict homeless density at a community scale. Please read the note from LAHSA below regarding the tract level counts. In this layer LAHSA's tract-level population count was rounded to the nearest whole number, and density was determined per square mile of each community. It should be noted that not all of the sub-populations captured from LAHSA (eg. people living in vans, unaccompanied minors, etc.) are not captured here; only sheltered, unsheltered, and total population. Data generated on 12/2/20.Countywide Statistical AreasLos Angeles County's 'Countywide Statistical Areas' layer was used to classify the city / community names. Since this is tract-level data there are several times where a tract is in more than one city/community. Whatever the majority of the coverage of a tract is, that is the community that got coded. The boundaries of these communities follow aggregated tract boundaries and will therefore often deviate from the 'Countywide Statistical Area' boundaries.Note from LAHSALAHSA does not recommend aggregating census tract-level data to calculate numbers for other geographic levels. Due to rounding, the census tract-level data may not add up to the total for Los Angeles City Council District, Supervisorial District, Service Planning Area, or the Los Angeles Continuum of Care.The Los Angeles Continuum of Care does not include the Cities of Long Beach, Glendale, and Pasadena and will not equal the countywide Homeless Count Total.Street Count Data include persons found outside, including persons found living in cars, vans, campers/RVs, tents, and makeshift shelters. A conversion factor list can be found at https://www.lahsa.org/homeless-count/Please visit https://www.lahsa.org/homeless-count/home to view and download data.Last updated 07/16/2020

The PCCF+ is a SAS© control program and set of associated datasets derived from the PCCF, a 2016 postal codeOM population weight file, the Geographic Attribute File, Health Region boundary files, and other supplementary data. PCCF+ automatically assigns a range of Statistics Canada standard geographic areas and other geographic identifiers based on postal codesOM. PCCF+ differs from the PCCF in that it: Uses population-weighted random allocation for many postal codesOM that link to more than one geographic area. Options are available for institutional postal codesOM. Procedures are included to link partial postal codesOM to geographic identifiers where possible. Problem records and diagnostics are provided in the program output, along with reference information for possible solutions. The geographic coordinates, which represent the standard geostatistical areas linked to each postal codesOM on the PCCF, are commonly used to map the distribution of data for spatial analysis (e.g., clients, activities). In April 1983, the Geography Division released the first version of the PCCF, which linked postal codes to 1981 census geographic areas and included geographic coordinates. PCCF+ was first created using the 1986 census and has been updated regularly with population weight files calculated for each census from 1991 through 2016. The purpose of the PCCF+ is to provide a link between six-character postal codesOM produced by the Canada Post Corporation (CPC), standard 2016 Census geographic areas (such as dissemination areas, census subdivisions, and census tracts) produced by Statistics Canada, and supplementary administrative areas and neighbourhood income quintiles. Postal codesOM do not respect census geographic boundaries and so may be linked to more than one standard geographic area, or assigned to more than one set of coordinates. Therefore, one postal codeOM may be represented by more than one record. The PCCF product, produced by Statistics Canada, provides links between postal codes and all recorded matches to census geography. PCCF+ uses the PCCF but provides additional functionality in that it uses a population-weighted matching process for some residential postal codesOM where more than one geographic code is possible. PCCF+ also provides routines for institutional postal codesOM and for historic postal codesOM. The purpose of this product is not to validate postal codesOM or the PCCF.

This web service contains a polygon layer that depicts fused air quality predictions for 2012, 2013, and 2014 for census tracts in the conterminous United States. Fused air quality predictions (for ozone and PM2.5) are modeled using a Bayesian space-time downscaling fusion model approach described in a series of three published journal papers: 1) (Berrocal, V., Gelfand, A. E. and Holland, D. M. (2012). Space-time fusion under error in computer model output: an application to modeling air quality. Biometrics 68, 837-848; 2) Berrocal, V., Gelfand, A. E. and Holland, D. M. (2010). A bivariate space-time downscaler under space and time misalignment. The Annals of Applied Statistics 4, 1942-1975; and 3) Berrocal, V., Gelfand, A. E., and Holland, D. M. (2010). A spatio-temporal downscaler for output from numerical models. J. of Agricultural, Biological,and Environmental Statistics 15, 176-197) is used to provide daily, predictive PM2.5 (daily average) and O3 (daily 8-hr maximum) surfaces for 2012, 2013, and 2014. Summer (O3) and annual (PM2.5) means calculated and published. The downscaling fusion model uses both air quality monitoring data from the National Air Monitoring Stations/State and Local Air Monitoring Stations (NAMS/SLAMS) and numerical output from the Models-3/Community Multiscale Air Quality (CMAQ). Currently, predictions at the US census tract centroid locations within the 12 km CMAQ domain are archived. Predictions at the CMAQ grid cell centroids, or any desired set of locations could be provided if needed. Predictions are not provided on December 31st of any year because complete daily CMAQ output are not available on those days after conversion of GMT to local eastern time.