Tag Archives: Census block

Census 2020 P.L. 94-171 Redistricting Data Updates

.. we are just two years away from the first census block level data from Census 2020.  The initial block level data will be the P.L. 94-171 redistricting data.  But before that, the initial Census 2020 TIGER/Line shapefiles/GIS files, the geography, will become available in November 2020, maybe earlier.  Stakeholders will be able to see how block and tract codes and geography have changed in many areas since 2010.  The prototype P.L. 94-171 data (see final file layout and subject matter items) are expected in the last week of March 2019 and will cover the Providence County, RI area. This post shows illustrative views and related details about the area. The Census 2020 P.L. 94-171 program and plans are reviewed in this Federal Register notice.

The applications/views shown below have been developed using the ProximityOne CV XE GIS software and related GIS project.

Census 2020 Data Access and Use Program
ProximityOne operates a comprehensive Census 2020 Data Access and Use Program providing tools to integrate and analyze these data with other data for redistricting, planning, evaluation, management, general analysis and policy-related applications. Contact us for more information; mention Census 2020 Data Access and Use Program in text section.

Providence, RI Census 2020 P.L. 94-171 Prototype
The Census 2020 P.L. 94-171 prototype covers Providence County, RI, part of the Providence-Warwick, RI-MA MSA (39300) — see Situation& Outlook report. Providence County is shown with cross-hatch pattern in the following graphic.

The next graphic shows a zoom-in to the county with cities/places shown with green fill pattern.

The next graphic shows patterns of economic prosperity for the county based on ACS 2017 median household income by census tract — blue, higher and red, lower.

The next graphic shows Census 2010 blocks for the county. Demographics described in the P.L. 94-171 file described about will be provided at the census block level.

Census block boundaries are primarily defined by roads. Providence County roads are shown in the next view.

The next view shows a zoom-in to the downtown Providence city area. Census blocks are shown with red boundaries and labeled with the 15-character U.S. national scope unique census block code. The pointer is located in census block 440070012001001, or 44-007-001200-1001, expressed as SS-CCC_TTTTTT-BBBB. Access these Census 2010 data (an example) using the Census FactFinder tool via this link. This is the “P1 RACE” table. The Census 2010 population of the block was 598. This census block is one of 13,597 Census 2010 census blocks comprising Providence County.

Rhode Island 116th Congressional Districts 01 and 02 (labeled) split Providence city (cross-hatch pattern) as shown in the graphic below. Pointer shows CD boundary.

Similar to above, the graphic below shows census blocks in context of Providence city (bold green boundary) and CDs 01 and 02.

Next Steps
This section provides a geographic orientation the Census 2020 P.L. 94-171 prototype area. A subsequent post (March 2019) will extend on this post with Census 2020 P.L. 94-171 data and related details. Use the downloadable project and software to examine geodemographics and redistricting operations.

Data Analytics Web Sessions
See these applications live/demoed. Run the applications on your own computer.
Join me in a Data Analytics Lab session to discuss more details about accessing and using wide-ranging demographic-economic data and data analytics. Learn more about using these data for areas and applications of interest.

About the Author
— Warren Glimpse is former senior Census Bureau statistician responsible for innovative data access and use operations. He is also the former associate director of the U.S. Office of Federal Statistical Policy and Standards for data access and use. He has more than 20 years of experience in the private sector developing data resources and tools for integration and analysis of geographic, demographic, economic and business data. Contact Warren. Join Warren on LinkedIn.


Mapping Urban/Rural Patterns by Census Block

Knowing about a geographic area by its urban/rural status is important for many reasons … the Federal Communications Commission (FCC) requires service providers to identify their deployment areas by census block. Internet service provider incentive programs exist that are geared toward rural areas. Telcom businesses increasingly use census block geography to determine/analyze markets. The related FCC E-Rate program uses urban/rural status to manage rate structures. Many Federal transportation programs rely on a clear distinction between urban and rural areas. Businesses might be interested in reaching markets that are predominantly rural versus suburban versus urban. Emergency service operations may differ by urban/rural status for many regions; being able to plan for low density population areas can be essential. There is a long list of reasons for importance, not the least of which are the societal implications as the U.S. continues to become more urban and less rural.

Based on the Census Bureau urban/rural definition, the Census 2010 U.S. urban population was 249,253,271 (80.7%) and the rural population was 59,492,276 (19.3%). The Census Bureau urban-rural classification is a delineation of geographical areas identifying both individual urban areas and rural areas of the nation. Urban areas are densely developed territory, and encompass residential, commercial, and other non-residential urban land uses. The Census Bureau does not identify geographic areas as “suburban.” There is no Census Bureau classification for suburban areas or suburban population. We will cover the topic of suburban areas and suburban population in the near future. More about the urban population.

About this Section
This section is focused on use of GIS resources to visually analyze patterns of urban/rural geography based on Census 2010 census blocks. We review census block level geography and urban/rural status in the context of a metro, an urbanized area, a city/place, a school district, and census tract. Applications illustrated here make use of the Austin-Round Rock, TX metro; similar views/applications may be developed for any county or metro. Members of the ProximityOne User Group ( join now, no fee) may use the GIS software and project files to create similar and more detailed views/analyses. After installing CV XE GIS Windows CV XE GIS installer, expand the GIS project (userid required) to c:\cvxe\1\; start CV XE GIS; open the GIS project c:\cvxe\1\austinblks1_tract.gis.

See related Web page for more details about the GIS project.

Defining Urban/Rural Geography and Census Blocks
For Census 2010, an urban area is a densely settled core of census tracts and/or census blocks that meet minimum population density requirements, along with adjacent territory containing non-residential urban land uses as well as territory with low population density included to link outlying densely settled territory with the densely settled core. To qualify as an urban area, the territory identified according to criteria must encompass at least 2,500 people, at least 1,500 of which reside outside institutional group quarters. There are two types of urban areas:
• Urbanized Areas (UAs) of 50,000 or more people
• Urban Clusters (UCs) of at least 2,500 and less than 50,000 people
As of Census 2010, there were 3,573 urban areas comprised of 486 urbanized areas (UAs) with population 219,922,123 and 3,087 urban clusters (UCs) with population 29,331,148.

Rural encompasses all population, housing, and territory not included within an urban area.

A census block is the smallest geographic tabulation area and is classified as either all urban or all rural. More about census blocks.

Austin-Round Rock Metro by Census Block
In the following view, blocks with the orange fill pattern shows all census blocks classified as urban in the metro; rural blocks have a gray fill pattern.
This view is developed by setting the block layer query to UR10=’U’.

Click graphic for larger view. View created using CV XE GIS and related GIS project. Use the GIS project to create similar views. Zoom to an area of interest. Add name, codes, or data values as labels. Add other geography. A selection of possibilities is shown below.

Austin-Round Rock Urbanized Area by Census Block
Blocks with the orange fill pattern comprise the Austin-Round Rock Urbanized Area. This view is developed by setting the block layer query to UACE10=’04384′ (urban section).

Click graphic for larger view.

Austin City by Census Block
Blocks with the orange fill pattern are urban blocks within Austin city.
This view is developed by setting the block layer query to UR10=’U’ and place=’05000′ (urban section).

Click graphic for larger view.

Austin ISD School District by Census Block
Blocks with the orange fill pattern are urban blocks with the Austin ISD school district.  This view is developed by setting the block layer query to SDUNI=’08940′ and ur10=’U’ (urban section).

Click graphic for larger view.

Travis County Census Tract “19.14” by Census Block
The next view shows a zoom-in to census tract “19.14” in Travis County, TX. See more about census tracts. Blocks with the orange fill pattern are urban blocks; rural blocks have a gray fill pattern. This view is developed by setting the block layer query to SDUNI=’08940′ and ur10=’U’ (urban section). The Census 2010 total population is shown as a label for each census block.

Click graphic for larger view.

Support Using these Resources
Learn more about accessing and using decision-making data; examine characteristics and patterns for your study areas and applications. Join us in a Decision-Making Information Web session. There is no fee for these one-hour Web sessions. Each informal session is focused on a specific topic. The open structure also provides for Q&A and discussion of application issues of interest to participants.

School Location Analysis

Goto ProximityOne  Location-location-location … this section illustrates use of GIS tools to develop custom maps showing location of points of interest, based on addresses, in context of other geography and patterns. Anyone with Internet access and a Windows-based computer can develop location analyses shown in this section for locations of interest anywhere in the U.S.

Starting at the end of this post, the objective is to display/examine the address in the context of related geography as shown in the graphic below.  The location, address, is shown by the red marker in context with street (and mini-profile of the street segment) and associated census block (red boundary, yellow census block code). The Koko Head Elementary School  address (189 Lunalilo Home Road, Honolulu, HI 96825) is used in this example. It could be any school in the U.S. or any address, school or otherwise. The view and details are reviewed in more detail below.

Examining Location/School in Context of Neighborhood
While there are many Web-based resources to obtain a map view of the location based on the address, and/or attributes of the school based on name, resources reviewed here provide a more flexible and comprehensive way to examine a location/school in context of the neighborhood and surrounding area demographics.  This process requires the types of resources reviewed here.

Study Area
The study area is in the vicinity of Hanauma Bay located west of Waikiki Beach in Honolulu, HI. The steps illustrated here can be similarly applied to anywhere in the U.S.

The next graphic shows a zoom-in view of the study area.  The coastline edge is shown with a line-shapefile that depicts perennial water features.

Geocoding: Assign Latitude-Longitude & Census Block Code
The address is entering into the CV XE GIS Find Address tool input box:
Clicking OK, a point shapefile is automatically created and added to the active GIS project. The next graphic shows the address location as a red marker.  The Identify tool is used to show the results of the geocoding.  Clicking on the marker displays the mini-profile.  The census block code is 150030001141014 or 15-003-000114-1014.  The address is located in FIPS state code 15, FIPS county code 003, Census 2010 census tract code 000114, and Census 2010 census block code 1014.  For other potential geo-referencing purposes, and as shown in the mini-profile, the latitude-longitude values are also retained in the shapefile dbf record.

A zoom-in view shows the study area in more detail. Roads are shown as black lines; census blocks are shown with red boundaries.

Zoom-in Detail; Location in Context
The view shown below shows the location (red marker) in context of street location and in context of associated census blocks.  Census blocks are shown with red boundaries and show yellow census block codes as labels.  The school is located within census block 1014.  Selected attributes of the street segment are shown in the profile.  The left- and right-side from address and to address ranges are shown as well as the left-side and right-side ZIP code.  These left- and right-side attributes are available for any intersection-to-intersection street segment in the U.S.

Economic Prosperity by Neighborhood
The next graphic shows patterns of economic prosperity in the broader area.  Koko Head ES is shown by the red marker (see pointer).  The color-coded areas show patterns of median household income (MHI) based on block group geography.  Intervals and color codes are shown in legend at left of map.  Labels show the MHI by block group.  The gray area has population of 39; MHI estimate is not available.  The MHI estimates are based on 2011 ACS 5-year data.  A more comprehensive analysis could select from approximately 250 subject matter items by block group (view available items).

Resources and Using the Tools
A GIS project was developed using the CV XE GIS software (no cost, details below.   The GIS project is comprised of two public domain shapefiles: the TIGER/Line 2013 edges/roads and the TIGER/Line 2013 census blocks.  The address point location was determined by entering the address into the CV XE Tools>Find Address feature.  The Find Address feature determines the latitude-longitude and census block code for the location.  A point shapefile is dynamically created.  The project is then saved for subsequent re-opening and use.

The GIS project and tools used to develop views shown in this section are available to ProximityOne User Group members. Join now, no fee. Members may download the GIS project and dynamically create related view.  This application can serve as an example to develop similar applications for locations of interest.

Related Sections
Schools and School Districts Main Page.
Hawaii Demographics.

Next Steps
An upcoming post will delve deeper into using these smaller area geodemographics to develop and analyze neighborhood patterns and trends.  Join us in the upcoming December 17, 2013 one hour web session where we talk about using the ACS 2012 5-year demographics for small area analysis.  Those new data are scheduled to be released that day.

Homeownership Patterns by Census Block

The homeownership rate peaked in America in 2004 at approximately 69.2 percent.  Homeownership is defined as the percent of occupied housing units (households) that are owner-occupied.  The homeownership rate in 2013 is roughly the same as in 1995. The gradual decline continues.

        Homeownership Rate 1970Q1-2013Q3 not seasonally adjusted; based on CPS/HVS

The focus of this section is on creating thematic pattern map views depicting homeownership by census block for the Washington, DC area.  This section builds on the previous post Mapping Demographic Patterns: Census Blocks.

The starting place is where Mapping Demographic Patterns: Census Blocks left off — the required software and GIS project are installed on the computer.  The next step is to start the CV XE GIS software, open the DC GIS project and set the intervals for the thematic pattern views.

To compute homeownership, the minimum required data items/fields are the number of owner-occupied housing units and the number of housing units. By examining the Census 2010 SF1 table shells (xls), these items are found in Table H4. Tenure — owner/renter occupancy of occupied units (line 9259 in the xls file).  Looking at the  SF1 technical documentation (pdf) matrix section (sequential page 483, numbered page 6-321), it is determined that the items field needed are (H0040002 + H0040003) — owner occupied housing units and H0040001 (occupied housing units).  These items are already loaded into the DC block shapefile dbf.

Intervals are defined for the map view with queries that set blue to blocks with homeownership rate of 65% or more, orange to blocks with rate 50%-65% and red to population blocks with a rate below 50%.  Zero population blocks are set to gray.  The initial view shown below tells the visual story that more of Washington, DC has a homeownership rate below the national average than above the national average — and how these homeownership rate patterns are distributed by block.

Homeownership Rate by Census Block — Washington, DC

Zoom-in to area east of U.S. Capitol complex
— transparency set to 60% enabling “see through” of color patterns
— mini profile of blue block at pointer
— h0040001: 79 occupied housing units and 54 owner occupied housing units (h0040002+h0040003)


Similar thematic maps showing patterns of homeownership rate by census block may be created for any area in the U.S.  Procedures to access and use these no cost resources for Census 2010 Summary File 1 census block applications are summarized in the the APIGateway Guide.

In a future post, homeownership rates will be reviewed for all states and metros, 2008 through 2012, using annual American Community Survey (ACS) data.

Using Census 2010 Summary File 1 with API Technology

The Census 2010 Summary File 1 (SF1) contains the most detailed Census 2010 summary statistic data available that is tabulated at the census block  level.  The SF1 data are, and will continue to be, an important data resource throughout the 2010s and beyond. The scope of subject matter includes cross-tabulations of age, sex, households, families, relationship to householder, housing units, detailed race and Hispanic or Latino origin groups, and group quarters.

Skip the downloads!  Using pre-API technology methods, you would download the very large state by state zip files and proceed through a number of steps to use the data.  An alternative would be to use the Census Bureau FactFinder, but use of this tool is infeasible for most types of dataset development operations.

As an example, the Texas Census 2010 SF1 — view these data here (not recommended) — is contained in a 815 MB downloadable zip file. The zip file expands into a set of 48 files comprised of a geographic segment and 47 comma-delimited (CSV) structured files.  The expanded 48 files require 8.5 GB of space, still in CSV structure.  Specialized software is then required to transform these data into usable structures/data. This is for reference/history, we can now skip over using that enormous and complex to use data.

Using API Technology
How things change!  Use of API technology to access these data is reviewed in this section.  By using API-based applications, you can avoid downloading the very large SF1. This section reviews how you can use the APIGateway to develop a census block dataset. Many statistical programs and all popular geographies are supported by this tool, but the focus here is on census block demographics from Census 2010 SF1.

The next series of steps illustrate how to develop the sample dataset shown in the graphic presented below.  The graphic shows a spreadsheet oriented view of rows corresponding to census blocks and columns comprised of a census block geoid (the geocode and structured shorthand by which the geographic area is referenced) followed by columns/fields of selected SF1 items.

Washington DC tract 004100 SF1 extract

Using the CV XE APIGateway with Census 2010 SF1
Follow these steps to run through the demonstration application.  You can then use the APIGateway tool to process on geography and subject matter items of interest to you.

1. Install CV XE GIS Software
Use the CV XE GIS installer to install the software on your Windows computer.  Take all default settings.  More information about CV XE GIS.

2. Get Washington, DC GIS Project Files
Expand http://proximityone.com/dmd/2013_dc_dp.zip to folder c:\cvxe\1.

3. Start CV XE.  With CV XE running, start APIGateway
Use File>APIGateway from main menu bar.  The APIGateway form appears as shown below.


The Batch Extraction operation involves two steps.
1 – Click main menu Settings>Batch Operation and specify settings.
2 – Close the Setting form. Click Tools>Batch Extraction to start processing.

The Batch Operations setting form is shown below.
APIGateway Batch Extract Settings

These settings will operate with no modification.  To use these settings,  close the form and click Tools>Batch Extraction to start processing.  The output file c:\cvxe\1\blk_sf1_2010_p003p004.dbf is created (Output Dataset) and contains the fields shown in the Field Names edit box.  The output file created will contain ALL records that meet the criteria of the Control File Query (substr(geoid,1,11)=’11001004100′) and processing blocks contained in the Control File (c:\cvxe\1\tl_2013_11_tabblock_dp.dbf).  The graphic at the top of this section provides a partial view of the file created.

You can use this version of the APIGateway to create your own datasets for any area of the U.S.  The Batch Operation in this version operates only with Census 2010 SF1 block level data.  The full version operates with many types of source data and supports wide ranging geographic levels — including ACS block group level data.

See the APIGateway Guide for more details regarding operations.

Using the Dataset Generated
There are at least two main ways the output dataset can be used.
1 – the block level data may be aggregated/analyzed in a tabular manner.
2 – the dbase version of the output dataset is structured in a manner that can be immediately joined with a shapefile for mapping and geospatial applications.

More about the Sample Dataset
The first row of the dataset shows selected data for census block 11-001-004100-1000.  P0030001 is the fieldname/shorthand for Census 2010 total population.  You can see the list describing these items using the table shells (xls) — see table P3 in the xls file. Field/item.column p0030002 is the White alone population.  Field name spelling is nitpicky; one character missed, incorrect or out of place can cause an error.  See sequential page 184 (numbered page 6-22 in the matrix section)in the SF1 technical documentation (pdf) to view the exact spelling of the field names and an alternative view of the table structure.

Washington DC tract 004100 SF1 extract

See related post regarding Mapping Census Blocks.  The next post on using data generated by the APIGateway will be November 19,2013.

Mapping Demographic Patterns: Census Blocks

This section is one of a series on mapping demographics.  Here we start with a hands-on approach to making a map in the Washington, DC area focused on census blocks optionally superimposed on OpenStreetMap layer.  Subsequent sections will build on this base. We will get to the objective of enabling you to put your own address-related data on a map combined with data from Census 2010 and American Community Survey.  We will make the map view shown below in this session.  Details follow.

Census Blocks; Washington DC

Census Blocks; Washington DC

“A picture is worth a thousand words.”  So true.  But when it comes to “map pictures,” that is only the beginning.  Mapping/GIS tools offer the additional element of geospatial views and analysis.  One example is site analysis where, for example, a radius view around a location can be translated immediately into data such as size of market or size/nature of impact area.

As maps and mapping tools have proliferated the Internet, it remains elusive to develop good custom maps that convey patterns of interest.  Many organizations defer getting into these applications because they are viewed as complex and required specialized skills and staff.  Yet the benefits are enormous.  Decision-making can be enhanced in ways unparalleled by using tabular data.  As technology advances, tools become more complex; keeping up with change can be challenging.  Read ahead, we can enhance capabilities in an easy, no cost, expandable manner.

Census Blocks
Census blocks are the smallest geographic area for which Census Bureau data are tabulated.   The approximate 11 million Census 2010  census blocks cover the U.S. wall-to-wall.  A statistical geographic area defined for the decennial census decade, a census block averages 100 people.  In urban areas a census block is often the area covered by a familiar city block. Generally permanent from census to census, census blocks are given a unique identifier comprised of state code(2) + county code(3) + tract code(6) + block code(4). See examples in above view where census blocks are labeled with their GEOID/geocode.  More about census blocks.

1. Install CV XE GIS Software
Use the CV XE GIS installer to install the software on your Windows computer.  Take all default settings.  More information about CV XE GIS.

2. Get Washington, DC GIS Project Files
Expand http://proximityone.com/dmd/2013_dc_dp.zip to folder c:\cvxe\1.

3. Open Washington, DC GIS Project
With CV XE running, and steps 1 and 2 completed, use File>Open dialog.
Open the GIS project file c:\cvxe\1\2013_dc_dp.gis.  The view appears as shown below.

Washington DC 2013_dc_dp start-up view

Washington DC 2013_dc_dp start-up view

Optionally use a second GIS project … open the GIS project file c:\cvxe\1\2013_dc_kalorama.gis.  The view appears as shown below.

2013_dc_dp_kalorama start-up view

2013_dc_dp_kalorama start-up view

Next Mapping Demographics section will cover 1) navigating and interpreting map views and 2) how to generalize these steps … any county in the U.S. We will use the above project to show mini-profiles of census blocks:

illustrating mini-profile of census block (pointer)

illustrating mini-profile of census block (pointer)

The mini-profile is auto-copied to clipboard. Paste it into a spreadsheet as shown below.

census block profile pasted into Excel

census block profile pasted into Excel

The above profile shows a mini-profile for census block 11-001-004100-2003.  The UR10 status shows that it is urban.  Geocodes for other areas and population attributes are shown further down in the spreadsheet (some also shown in previous graphic).

The next post on Mapping Demographic Patterns will be November 19,2013.