The U.S. Census Bureau has designed a web mapping application called "Census Flows Mapper,"
an application that relies on American Community Survey, or ACS, 5-year estimates.
The Census Flows Mapper offers a variety of tools to query a dataset, tools to access
county statistics, data tables, information about the application, Frequently Asked Questions,
and a function to turn city locations and names on and off for additional spatial reference.
Additional tools in the left vertical pane of the interface allow users to generate a
map:
To select a county of interest, click the arrow on the drop-down menu to access a populated
list, click in the text field and type the name of a county, or click a county on the
map.
Select the "Map County Migration Flows" option to show data on the map.
The "Choose a dataset" radio buttons allows you to select a dataset.
The "Choose a type of migration flow" radio buttons allow the user to select "Net," "Outbound,"
or "Inbound."
The "Choose a characteristic" drop down menu allows the user to select socio-economic and
demographic characteristics by dataset.
Characteristics will differ by dataset.
The "Choose a color palette" drop down menu offers users a choice of preselected color
schemes for their map.
This color scheme is also reflected in the legend.
The "Choose a classification type" drop down menu allows the user to select one of three
breaks for the data: Natural Breaks, Quantile, and Equal Interval.
Here the "Quantile" break is reflected on the map.
The "Choose range of movers" slider shows the range of data and allows users to select
a sub-set of that data.
Clicking the "About This Map" tab opens a pop-up box containing instructional information.
Clicking on the "FAQ" tab opens a pop-up box of Frequently Asked Questions, which range
from general topics about ACS to more specific questions about migration and interpreting
the map.
Now let's refresh the settings and walk through a working example of a county in Flows Mapper.
In the "Search for a county or click on the map" text field, enter Maricopa County, Arizona
and select it from the list.
As the default, the map populates with the most current release of the "County-to-County
Migration Flows" data and the Net Migration for Maricopa County.
Maricopa County is outlined in red.
The "View County Statistics" tab reveals a pop-up box containing data about the county
currently selected for mapping.
The pop-up box can be moved to allow better visibility of the map and tools.
In the map area, the user can also zoom into a particular area of interest.
If you click on a different county, Coconino County for example, you see it becomes outlined
in blue, and a pop-up window shows that Maricopa County has lost a net of 832 people to Coconino
County.
By clicking on the shaded U.S. map button, the map returns to the original extent of
the map frame, but does not reset the map data.
With Maricopa County still selected, let's adjust the Color Palette and Classification
Type as we did a moment ago.
Click the "View Data Table" tab.
A pop-up window containing the data table for Maricopa County, Arizona opens.
This table contains State and County FIPS codes, County Names, State Names, and the
number of net movers for the selected county, in this case Maricopa County.
The pop-up window also contains an "Export to Excel" button, which allows users to download
the current data into an Excel spreadsheet.
The U.S. Census Bureau created "Census Flows Mapper" to make the U.S. county-to-county
migration data more accessible and easier to use for data users.
With this tool, data users can instantly customize maps and download data to quickly meet their
evolving needs.