First, a little lesson on the Fed. The Federal Reserve System is a centenary institution that

• sets the nation’s monetary policy
• supervises and regulates banking institutions
• maintains the stability of the financial system
• and provides financial services to depository institutions, the U.S. government, and foreign official institutions.

The Fed blends both centralized and decentralized decisionmaking, with the Board of Governors in Washington, D.C., and 12 independent Federal Reserve Banks across the nation to ensure the system works on a daily basis.

Our first FRED map (above) shows the resident population in each Federal Reserve District in 2021, each labeled with the city where the Reserve Bank is located. Hover over the map to see the thousands of persons in each District. The District boundaries were drawn in 1914, by the way, when the nation’s population was much different.

By default, the FRED map is set to show the range of data, from maximum to minimum, organized in five segments (or fractiles) calculated to contain a similar number of data points. Darker colors represent larger data values.

The population in the San Francisco District is by far the largest in the Fed System. In the map, it occupies, all by itself, the first segment. The remaining four segments include either two or three Districts each. (We tried, but dividing 12 Districts by 5 segments didn’t yield a whole number.)

The second FRED map shows the same data. But, instead of sorting the data into five segments with a similar number of data points, the data here are sorted into equal interval segments. That is, the range of data is the same size for all segments.

Once again, the San Francisco District occupies the top spot all by itself, but the second-largest data segment (slightly lighter shade of green) now includes only the Atlanta District.

As road maps help us navigate unfamiliar landscapes, FRED maps help us make sense of numbers by creating captivating color-coded comparisons between data points. Our choices in creating these data maps affect the story behind the numbers. To learn more about best practices, watch this webinar from the U.S. Census Bureau.

How these maps were created:
First map: Search FRED for “Resident Population in Federal Reserve District,” pick any District, and click the “View Map” button. Second map: Starting with the first map, click the “Edit Map” button and select “Data grouped by: Equal Interval.” To customize the interval colors, click on the colored squares to the left of each inequality sign and select your color: You have the whole rainbow to proudly choose from.

Suggested by Diego Mendez-Carbajo.