American Community Survey: Journey-to-Work Data Analysis

1. Journey-to-Work Data in the American Community Survey (ACS) May 17, 2009 TRB Transportation Planning Applications Conference Federal Data for Modelers Workshop Houston, TX Melissa Chiu, CTPP Coordinator Journey to Work and Migration Statistics Branch Housing and Household Economic Statistics Division U.S. Census Bureau

2. What is the American Community Survey? • A large, continuous demographic survey • Produces annually updated single-year and multi-year estimates of the characteristics of the population and housing • Produces characteristics, not a population count • Produces information for small areas including tracts, block groups and population subgroups - updated every year • Key component of reengineered 2010 census • Survey designed to include • U.S. stateside and Puerto Rico • Population in both housing units and group quarters

3. How Does the Sample Compare? • ACS samples every year and spreads sample over 12 months; census samples once a decade and uses the entire sample at the same time • ACS subsamples for personal visit follow-up; court ruled against census subsampling • Census sample estimates based on about 18 million housing units; ACS 5 year estimates based on about 11 million housing units

4. ACS Data Release Schedule Data products are released in the year following the single year or multiyear period in which data are collected.

5. December 2008: First Multiyear Estimates • Data collected 2005-2007 • Based on data from housing unit population in 2005-2007; group quarters population 2006-2007 • First release of ACS data for mid-sized counties, other areas • First release of two sets of ACS estimates for states, large counties, Congressional Districts, Public Use Microdata Areas (PUMAs) • Most data products similar to those of past years • Inflation-adjusted to 2007 • Geography based on January 2007

6. Web Site and Training • ACS Compass Products • Understanding and Using ACS Data: Handbook Series • Presentations • Slides and presentation notes • Various aspects of the ACS • On-line Tutorial • www.census.gov/acs/www/UseData/Compass/compass_series.html • Train the Trainer workshops at SDCs, regional offices, etc.

7. General Users Businesses High School Teachers Media Congressional Staff State & Local Governments Federal Agencies Researchers Rural Areas PUMS Users American Indians / Alaska Natives PRCS (in Spanish) Target Audiences for ACS Compass Handbooks

8. www.census.gov/acs/ Subscribe to the ACS Alert Information about the American Community Survey

9. Organization of ACS Data in the American FactFinder (AFF) • 1. Datasets (ACS, Census) • 2. Data year(s) • 3-year data products are the default • 1-year and 3-year data products distinguished • 3. Data products • 4. Specific tables or maps • Assistance links highlighted

10. Journey-to-Work ACS Data Products • Data products and prefixes B Base Detailed Table C Collapsed Detailed Table S Subject Table R Ranking Table (single-year only) GCT Geographic Comparison Table M Thematic Map • Commuting products are numbered “08” Example: B08xxx is a Base Table on commuting

11. Journey-to-Work ACS Data Products • Detailed Table examples (B08xxx / C08xxx): Means of transportation by worker characteristics Travel time by time leaving home Place of work for metropolitan, micropolitan, and non-metro/micro levels Vehicles available in household • Majority of tables available at both residence geography (B081xx, B082xx, B083xx) & workplace geography (B084xx, B085xx, B086xx)

12. Journey-to-Work ACS Data Products • Subject Tables same information as Detailed Tables but more user friendly format • Examples (S08xxx): Commuting characteristics by sex Means of transportation to work by selected characteristics - at residence geography - at workplace geography

13. Journey-to-Work ACS Data Products • Ranking Tables rank states for one measure • (R08xxx): Mean travel time to work Percent of workers who traveled to work … by car, truck, or van alone by carpool by public transportation Percent of workers who worked outside county of residence • For one-year data only

14. Journey-to-Work ACS Data Products • Geographic Comparison Tables cover samemeasures as Ranking Tables but for more geographies • Examples (GCT08xxx): Mean travel time to work for counties by U.S. state Percent of workers who traveled to work by carpool by place by U.S. state Percent of workers who worked outside county of residence by urban / rural, metropolitan and micropolitan area status

15. Journey-to-Work ACS Data Products • Thematic Maps allow users to design own maps of samemeasures as Ranking Tables • (M08xxx) • Can determine… Data classes: number and breaks Boundaries and features Level of geography - State - County - Congressional district - Metropolitan/ micropolitan statistical area - Public Use Microdata Area (PUMA)

16. factfinder.census.gov Data Products- American FactFinder

17. Organized by dataset then by data product Select Dataset and Product Type

18. List all Tables- Select “08” Products

19. Many ways to select geography Geography is hierarchical: First select type of geography, then specific area. Select Geography

20. Click “Data Sets” to change data product Print, download, save or load a query Change year, geography, subject table Subject Table- Example (S08xxx)

21. Select geo type, e.g. urban, rural, metro, principal city Change to collapsed version Can select multiple areas for detailed tables Can select multiple detailed tables too (scroll down) Detailed Table- Example (B08xxx/C08xxx)

22. Download to get all geographies and tables at once Click Next to see other geographies selected Detailed Tables- Geo Components(down to state only)

23. Download- Example

24. Can sort by rank or by state Ranking Table- Example (single year only)

25. Geographies or geo components within nation or state only Geographic Comparison Table- Example (GCT08xxx)

26. Thematic Map- Example (M08xxx)

27. Thematic Map- Options • Statistical significance view • Select a geography • Displays all areas that are statistically significantly different from the selected geography • Can save as .PDF file under “download” menu

28. Other Options in American Factfinder • Can create “Custom table” from the detailed tables • Data Download Center • - Download selected ACS tables for all available geographies at one time • Can “Download PUMS data” file for microdata

29. Data Download Center • Download large amounts of ACS data • Geographic units • Total U.S. • States • Counties • Places • CBSAs (Metro and Micro Areas) • Congressional Districts • All areas meeting minimum population threshold

30. Data Download Center • ACS Tables (Selected) • Base / Detailed tables • Data profiles • Subject tables • Choose up to 50 tables at one time • Download .zip file consisting of .txt files • README file • Geographic identifiers • Data- estimate and 90% MOE for each cell, all tables • Files pipe-delimited, can upload to Excel

31. On American FactFinder … Data Sets page on upper right …or left side bar Data Download Center- Example

32. Select Dataset Data Download Center- Example

33. Select one geographic level Select data product type Data Download Center- Example

34. Select up to 50 tables and ‘Add’ Click ‘Next’ to get to ‘Start Download’ then download a .zip file Data Download Center- Example

35. .Zip file includes a readme file on data values, geographic identifiers, and data file(s) Open data file in Excel as ‘Delimited’ by pipe: | Data Download Center- Example

36. U. S. Census Bureau • Melissa Chiu, CTPP Coordinator • Journey-to-Work & Migration Statistics Branch • Housing and Household Economic Statistics • 301-763-2421, -2454 • melissa.c.chiu@census.gov • www.census.gov/population/www/socdemo/journey.html