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Commuting and Migration Data Products from the American Community Survey
Journey-to-Work and Migration Statistics BranchU.S. Census Bureau
State Data Center Steering Committee Meeting, Feb. 2011
Geographically Dependent Characteristics: “Flows”
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Commuting
Migration
Flow Data in the ACS
• The ACS asks about: - Place of work - Residence 1 year ago
• Each question tells a story about 2 geographies
• AFF currently cannot support flow products
• The Challenge - Disseminating useful and accessible flow data that protects the confidentiality of respondents
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Past Efforts to Present Flow Data
• Large matrices that provide counts linking origins and destinations– Number of characteristics limited to protect
confidentiality– Tables are cumbersome and difficult for AFF to
accommodate
Tables showing data for only one end of the flow– More characteristics available– Limited utility due to less geographic specificity about
other end of flow
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Census Bureau’s Internal Flows Working Group
• New internal group formed to create new and modified flow products to become part of standard production
• Focus on data content and dissemination method
• Considerations for new product development: User needs, DRB rules, content of existing products (e.g., EEO special tab)
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Proposed Approach for Presenting Flows: Alternate Characteristics
across Years• Release new set of flow data each year based on
5-year ACS data (county-to-county level)
• Initial release will only include counts
• Each subsequent annual release within a 5-year period to include flows crossed with a small number of characteristics that vary by year
• Achieve a set of flows by multiple characteristics over the course of 5 years
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For Example:
• Year 1: Basic count of county-level worker flows
• Year 2: Worker flows by age and sex (separately)
• Year 3: Workers flows by race and Hispanic origin
• Year 4: Worker flows by means of transportation
• Year 5: Worker flows by Industry and Occupation
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We Want Your Feedback• Which characteristics are most important to flow
data?
• Among existing ACS migration and place of work tables on AFF, which are least useful?
• How do you want to obtain the data? – Geo-IDs such as FIPS codes included in table?– Utility of maps to accompany data tables?
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Home-to-Work Flow Products
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POW Flows and Metro/Micro Area Definitions
• Place of Work flows are used to support delineation of Metropolitan and Micropolitan Statistical Areas for OMB
• Metro and Micro areas are made up of a county with a large population nucleus and adjacent counties that have a high degree of integration with that nucleus
• Integration among counties is, in part, measured by county-to-county commuter flows
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POW Flows and Metro/Micro Areas cont.
• County-to-county home-to-work flows based on 5-year ACS 2006-2010 will be released to support metro area definitions
• Released every 5 years with no characteristics
• 2000 Census County-to-county home-to-work flows available at:
<http://www.census.gov/population/www/cen2000/commuting/index.html>
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Residence County to Workplace County Flows for NevadaSorted by Residence State and CountyRes
StateRes
CountRes
(C)MSRes
PMSAResidence
State- County Work State
Work County
Work (C)MS
Work PMSA
Workplace State-County Name Count
32 003 4120 9999 Clark Co. NV 001 089 3440 9999 Madison Co. AL 632 003 4120 9999 Clark Co. NV 001 101 5240 9999 Montgomery Co. AL 2032 003 4120 9999 Clark Co. NV 001 103 2030 9999 Morgan Co. AL 532 003 4120 9999 Clark Co. NV 001 117 1000 9999 Shelby Co. AL 1132 003 4120 9999 Clark Co. NV 002 016 9999 9999 Aleutians West Census Area AK 2632 003 4120 9999 Clark Co. NV 002 020 0380 9999 Anchorage Municipality AK 2432 003 4120 9999 Clark Co. NV 002 185 9999 9999 North Slope Borough AK 932 003 4120 9999 Clark Co. NV 004 013 6200 9999 Maricopa Co. AZ 47932 003 4120 9999 Clark Co. NV 004 015 4120 9999 Mohave Co. AZ 1,50132 003 4120 9999 Clark Co. NV 004 019 8520 9999 Pima Co. AZ 3032 003 4120 9999 Clark Co. NV 004 021 6200 9999 Pinal Co. AZ 4432 003 4120 9999 Clark Co. NV 004 025 9999 9999 Yavapai Co. AZ 1732 003 4120 9999 Clark Co. NV 004 027 9360 9999 Yuma Co. AZ 332 003 4120 9999 Clark Co. NV 005 007 2580 9999 Benton Co. AR 732 003 4120 9999 Clark Co. NV 005 081 9999 9999 Little River Co. AR 1232 003 4120 9999 Clark Co. NV 005 119 4400 9999 Pulaski Co. AR 732 003 4120 9999 Clark Co. NV 006 001 7362 5775 Alameda Co. CA 15032 003 4120 9999 Clark Co. NV 006 009 9999 9999 Calaveras Co. CA 1832 003 4120 9999 Clark Co. NV 006 013 7362 5775 Contra Costa Co. CA 3132 003 4120 9999 Clark Co. NV 006 019 2840 9999 Fresno Co. CA 2332 003 4120 9999 Clark Co. NV 006 023 9999 9999 Humboldt Co. CA 832 003 4120 9999 Clark Co. NV 006 027 9999 9999 Inyo Co. CA 732 003 4120 9999 Clark Co. NV 006 029 0680 9999 Kern Co. CA 36
American Community Survey 2006-2010 Special EEO Tabulation
• Special Equal Employment Opportunity (EEO) Tabulation
• Home-to-work flows by industry/occupation and several demographic characteristics
• Released in late 2012 via AFF
• Subject Matter Variables: detailed occupation categories, race and ethnicity, citizenship, sex, educational attainment, older age groups, younger age groups, industry and earnings
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American Community Survey 2006-2010 Special EEO Tabulation
• Types of tabulations: – worksite tabulations – workflow tabulations for a central worksite showing
the flow to that worksite of workers from up to nine individual counties, places, or balance of counties
– residence tabulations
• Geographies:– nation, states, CBSAs, counties, county sets, and
places
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LED/OnTheMap
• Local Employment Dynamics (LED)
• Home-to-work flows using Quarterly Census of Employment and Wages records
• OnTheMap allows users to map small-area job counts and travel patterns, including home-to-work flows.
• http://lehdmap.did.census.gov/
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Census Transportation Planning Products (CTPP)
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What is the CTPP? A set of special tabulations from the American Community Survey tailored for the data needs of transportation planners
Produced by the Census Bureau, sponsored and owned by American Association of State Highway Transportation Officials (AASHTO)
3-Year Census Transportation Planning Products
3-year CTPP Data Product
Available Now
Based on ACS 2006, 2007, 2008
Available for areas of 20,000 population or greater
http://trbcensus.com/products
The 3-year CTPP Design
Based on 2000 Geography
MSA – EACH Principal CityMetropolitan Statistical Area
POW PUMAPUMAPlaceMCD
County
Nation (US Total)
Product Structure
3-PartsPart 1- Place of Residence
Part 2- Place of Work
Part 3- Flows between Home and Work
State
Product documentation available at: http://ctpp.transportation.org/Documents/CTPP_custom_tabulations_based_on_3yracs2006_2008.xls
Key CTPP Contacts
• Penelope WeinbergerAASHTO CTPP Program [email protected]
http://ctpp.transportation.org
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Forthcoming Commuting Report
“Commuting in the United States: 2009”
More information on commuting special products can be found at:
<http://www.census.gov/population/www/socdemo/journey.html>
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Overview of ACS-Based Migration Products
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Decennial Census Products
Census 2000 Migration Data DVD
County-to-County Tables:1 general table– no restrictions
19 single characteristic tables – rounding
22 multiple characteristic tables - rounding & restricted to flows of 3 or more unweighted cases
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ACS Migration Flow Products
•ACS State-to-State Migration Flow Tables Published since 2005
• Shows state of current residence by state of residence 1 year ago (no characteristics)
• NOT a part of standard products
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2008 and 2006-2008 state-to-state migration tables now available:
http://www.census.gov/population/www/socdemo/state-to-state.html
Possible Future 5-Year Migration Products
*County-to-County migration flows (2006-2010)
*limited characteristics
May also produce:
Place-to-Place
MCD-MCD (12 states)
MCD-to-County
County-to-MCD
CBSA-to-CBSA
Metro Area-to-Metro Area
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Standard Migration Products in AFF
Tables with In-Migration by Characteristics• Since 2004 ACS• All publishable geographies
Tables with Out-Migration by Characteristics• Since 2007 ACS• Limited geographies
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Crossed for AFF Migration Tables
• Age• Sex• Race/Hispanic
Origin• Citizenship• Marital Status
• Educational Attainment
• Individual Income• Poverty Status• Tenure
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Issues• Smaller sample size• Fewer movers (residence 1 year ago vs. 5 years ago question)• Larger margin of errors• Periodicity – new data each year
•Disclosure issues• Overlapping datasets• More standard data products• 50 case limit on residence 1 year ago tables
• Not part of basic production
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Similar Problem: Journey to Work• Census Transportation Planning Products
– Previously created tables of characteristics, and Home to Work Flows by characteristics from decennial data
– ACS 3-year CTPP just released– # of crosses for flows minimized to 5 variables due
to disclosure avoidance requirements– Disclosure issues will still be an issue for an ACS 5-
year CTPP product being planned
Current remedy – Synthetic Data Approach
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Forthcoming Migration Report and other products
“Geographic Mobility: 2008-2009”
• More information on migration special products can be found at:
• www.census.gov/population/www/socdemo/migrate.html
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U.S. Census Bureau: Journey-to-Work & Migration Statistics Branch
Contact: Alison FieldsPhone: 301-763-2454
Email: [email protected]
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