Tutorials

Step-by-step tutorials for working on mapping projects using GIS methods and software.

View the Project on GitHub HarvardMapCollection/tutorials

How to Obtain Census Data for GIS Mapping

Sometimes new mappers are tripped up by census data, because in order to make a map, you need to download two separate census files:

  1. A table of statistics
  2. A geography boundary file

Sources

In this lesson, you will learn how to get these files from your choice of the following sources.

Social Explorer

NHGIS.org

Either choice will provide you with census data well-tailored for GIS methods. We recommend using one of these sources for digital mapping, as opposed to downloading directly from The U.S. Census Bureau portal.

Example data

Geography tip: Census tracts are a popular aggregation unit, as they are more granular than county or state level data, but more available and statistically-reliable than block level data.

The steps in this tutorial series will work for any U.S. census data, such as age, race, income, etc. If you’re not sure which variables are available, you can use censusreporter.org to find out.

Screenshot of final map, showing renter occupied units in Somerville and Cambridge Example of the tenure data we will work with, uploaded to ArcGIS Online.

Obtaining via Social Explorer

  1. Visit your institution’s Social Explorer. Here is the link for Harvard’s Social Explorer.

  2. If you have an account, log in. Otherwise, you’ll have to make one.

  3. On the Social Explorer landing page, select Tables from the left-hand menu. Screenshot of Tables button on Social Explorer

  4. Since the housing variable is not collected in the full count every ten years, we need to refer the more detailed surveys collected of sample populations on a rolling basis, called the American Community Survey (ACS). Select American Community Surveys (5-Year Estimates).

  5. Click Begin Report next to the 2015-2019 estimates.

  6. Under Select a Geographic Type choose 140...Census Tract from the dropdown menu.

  7. Under Select a State choose Massachusetts from the dropdown menu.

  8. Under Select one or more geographic areas and click ‘add’ select All census tracts in Massachusetts.

  9. Select Add. Screenshot of Add button on Social Explorer

  10. Select Proceed to Tables.

  11. Under Select one or more tables and click ‘add’ scroll down and select A10060: Tenure.

  12. Select Add. Screenshot of Add button on Social Explorer

  13. Select Show Results.

  14. Navigate to the Data Download tab. Screenshot of report tabs on Social Explorer

  15. Under Download data by geography type select Census Tract data (CSV) and the tabular statistical data will download to your computer.

  16. Under Download programs to import and label data select Data dictionary (text file) in order to interpret the dataset.

  17. Close out of the report screen by clicking the X in the upper-left corner next to Create Report. Screenshot of close button on Social Explorer

  18. Now from the main menu, select Geodata.

  19. Scroll down and select U.S. Tract 1910-2019.

  20. Under TRACT 2019 US SL140 Coast Clipped select the button that reads Shapefile to download the GIS data you will need for mapping.

You are now ready to move on to the next skill, How to join data in QGIS.

Obtaining via NHGIS.org

  1. Visit NHGIS.org.

  2. Select Get Data. Screenshot of Get Data button on NHGIS.org

  3. Select Topics. Screenshot of Topics facet on NHGIS.org

  4. Select Housing. Screenshot of Housing topic facet on NHGIS.org

  5. Check off Tenure and Mortgage Status. Screenshot of Tenure and Mortgage Status topic checked off on NHGIS.org

  6. Finalize your topics selection by choosing the Submit button. Screenshot of Submit button on NHGIS.org

  7. To specify we want to work with census tracts, select Geographic Levels. Screenshot of Geographic Levels facet on NHGIS.org

  8. Check off Census Tract. Screenshot of checked-off census tract option on NHGIS.org

  9. Finalize your geographic levels selection by choosing the Submit button. Screenshot of Submit button on NHGIS.org

  10. To indicate our time frame of 2015-2019, select Years. Screenshot of Years facet on NHGIS.org

  11. Check off 2015-2019. Screenshot of checked-off 2015-2019 option on NHGIS.org

  12. Finalize your years selection by choosing the Submit button. Screenshot of Submit button on NHGIS.org

  13. Under Source Tables, check off the Tenure data table. This will add the census statistical table to our shopping cart. Screenshot of checked-off tenure table on NHGIS.org

  14. To change the results that match our criteria from tables to GIS boundary files, select GIS Files.

    Remember, we need both! Screenshot of GIS files tab on NHGIS.org

  15. Checkout by selecting Continue from the data cart in the upper-right hand corner of the screen. Screenshot of data cart on NHGIS.org

  16. Accept all of the download defaults.

  17. Select Submit.

    You will need to create a free login in order to checkout. You can create one in a new tab if you don’t want to lose your data selection.

You are now ready to move on to the next skill, How to focus the data.

Tips