ArcGIS 10: Working with 2010 Census Data

NOTE:  This tutorial requires that you download the "Downloading AFF Data" guide from the US Census.

ArcGIS 10: Working with 2010 US Census Data

Finding Boundary Files (and giving them a spatial reference)

1. Navigate to the US Census Website
2. Click “Geography” at the top of the page
3. Click the TIGER link; then choose “Cartographic Boundary Files”
4. Locate and Download the Boundary Files for 2000 Census Washington State counties in shapefile format.
5. Unzip and Load the shapefile.
6. What coordinate system is it using? Ooops… No coordinate system.
7. Open ArcCatalog. (may need to refresh the folder)
8. Set GCS to NAD1927 (note that the USFS uses this)
9. Close ArcCatalog
10. Reproject using Dataframe Properties: select NAD1927 State Plane, WA
11. Click “full extent” button
12. Check out the attribute table. Turn labeling on and remove duplicate labels for counties.
13. Save this map as “WA counties.mxd”

Finding and Joining 2010 Census Demographic Data

1. Return to the Census Home Page and click “Geography”
2. Go to the TIGER page and click “TIGER/Line Shapefiles & Files”
3. Under “Previous TIGER/Line Shapefiles,” Click on “2010 TIGER/Line Shapefiles Main Page.”
4. In the yellow-ish box on the left, click on “Download Shapefiles.”
5. From the “Select a layer type” dropdown box, choose “Census Tracts”
6. Choose Washington State and then Thurston County 2010. Download the file to your work folder. Unzip it and load it into ArcMap.
7. Note the brief attribute table
8. Return to www.census.gov
9. Click “Data” (at the top of the page) and then “American FactFinder”
10. Introduce the concept of “summary files” and explain how the Census website has changed its interface to be “friendlier” (Hmmmm….)
11. Open “Topics” and then “People.” Note the various demographic choices.

12. Get Thurston Co, WA. Census tract data on race
     a. FIRST, ESTABLISH YOUR GEOGRAPHIC LEVEL
          i. Geographies>>Geographic Type: “census tract”
          ii. “Within State”: Washington
          iii. click “All census tracts within Thurston County, Washington”
     b. NEXT, CHOOSE YOUR DATA SET
          i. Topics>>People>>Race & Ethnicity>>Race & Ethnicity of Individual. Close the selection window.
          ii. In the big window, click “Race and Hispanic or Latino Origin: 2010”
          iii. Examine the resulting table

13. Download a zipped CSV file (do NOT download the Excel file)
14. Open the file in Excel and examine the contents.

15. What do the categories actually mean???
     a. Expand all columns by selecting all and then using Format>>Columns>>Autofit Selection
     b. Go through process of editing the Excel file to meet DBF standards (only one row of headers; header labels 10 characters only, with no special characters except underscores)
     c. SAVE as an XLS or XLSX file
     d. CLOSE EXCEL

16. Open boundary file in ArcMap
17. Open attribute table

18. LOOK FOR CENSUS CODES THAT MATCH THOSE IN THE DOWNLOADED RACE DATA FILE
     a. Answer: the Geo.id2 field is a match with the GEOID10 column in the Attribute Table
     b. BUT---the Geo.id2 field is a “Number” format, while GEOID10 is a “String” (or Text) format!!!! This will not do….

19. CREATE A COLUMN IN THE FACTFINDER FILE TO BE A “TEXT” COLUMN THAT MATCHES the GEOID10 COLUMN
     a. follow the directions in the Census PDF: DownloadingAFFData.pdf, starting with Page 11.

20. In ArcMap, right click the layer and choose “Joins and Relates”
21. Keep all records
22. Join the layer to your FactFinder data file using the appropriate matching columns
23. Create your map using your new data