Using Census Data to Map Change
A growing number of organizations (including the Census Bureau) are producing census-based interactive maps that allow users to choose the level of geography, topic or time period they want to display. Interactive maps showing 2000-2010 race and ethnic population change at the neighborhood level for 10 large cities and their suburbs were launched recently by the Center for Urban Research at the CUNY Graduate Center. These maps–as well as others linked to below–are a vivid and dynamic way to show patterns of demographic change.
The Center for Urban Research maps, based on data from the 2000 Census and 2010 Census, display the predominant race or ethnic group at the block level in these urban regions–Baltimore, Boston, Chicago, Houston, Los Angeles, New York, Philadelphia, Phoenix, San Francisco and Washington, D.C. Additional metropolitan areas will be added this summer, including Atlanta, Charlotte, Detroit, Las Vegas and Miami.
The map displays Census 2000 data on the left and Census 2010 data on the right; users can toggle between the two by moving a vertical bar across the map, and can zoom in or out. Clicking on the map brings up detailed counts for a block. (See “About” for instructions.) A detailed block-level geographic file for New York can be downloaded from the site, and data for other cities can be requested from the Center for Urban Research.
Other map options include:
- The Census Bureau has released an interactive population map with basic and household data from the 2010 Census, as well as links to the data. There’s a page on the bureau website that also shows maps of redistricting and population counts that allow users to mouse over a state to see change over time.
- A number of newspaper sites–including the New York Times, USA Today and Washington Post–put up maps with Census 2010 data for the nation about change in population, race or ethnic groups, density and other variables. The Times also created a map with earlier American Community Survey data about populations, education, housing, income and same-sex couples.
- Social Explorer maps allow users to look at population density for 2010 Census tracts, as well as browse maps with earlier Census Bureau data. The Brookings Institution has an interactive map that uses data from the 2000 Census through the 2009 American Community Survey to show trends about population, immigration, households and other topics for metropolitan areas, cities, suburbs and states. The Pew Research Center has released interactive maps showing recent Hispanic population trends, as well as census data on geographic mobility and marriage and divorce.
Building an online map is easier than it used to be, but involves a number of complicated steps and choices. This make-a-map video tutorial on the Knight Digital Media Center website walks through the steps involved in constructing a map showing 2000 Census population numbers for San Francisco.