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 –Based on data from housing unit population in ; group quarters population –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 – Train the Trainer workshops at SDCs, regional offices, etc.

7 Target Audiences for ACS Compass Handbooks 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)

8 Information about the American Community Survey Subscribe to the ACS Alert

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 same measures 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 same measures 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)

Data Products- American FactFinder factfinder.census.gov

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

18 List all Tables- Select “08” Products

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

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

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

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

23 Download- Example

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

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

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

32 Data Download Center- Example Select Dataset

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

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

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

36 U. S. Census Bureau Melissa Chiu, CTPP Coordinator Journey-to-Work & Migration Statistics Branch Housing and Household Economic Statistics ,