If you’ve looked at FRED data, you’ve probably seen the term MSA, which is “metropolitan statistical area,” which the Census defines as “a core area containing a substantial population nucleus, together with adjacent communities having a high degree of economic and social integration with that core.” It’s that high degree of economic integration that can make MSAs more comprehensive and relevant than just the specific governmental boundaries of cities and counties. In fact, MSAs often span several counties and sometimes straddle state borders. Think of it as a commuting basin… Or create your own metaphor!
The GeoFRED map here shows population growth for MSAs: Red is at the strong end of the growth spectrum and dark blue is at the weak end. What’s behind these changes in population? The main drivers are moves between MSAs, moves from rural areas into MSAs, and immigration from abroad. In some years, the boundaries of some MSAs are adjusted and can lead to substantial increases. If you follow the “View on GeoFRED” link below the map, you can select different years and see migration patterns over time, which are affected by local economic conditions. Some MSAs, like New York–Northern New Jersey–Long Island, change pretty drastically from year to year. Other MSAs are steadier: For example, growth in St. Louis is consistently slow and growth in Las Vegas–Paradise is consistently fast.
How this map was created: On FRED, search for the population of any MSA you can think of: Choose one of the larger U.S. cities, and the MSA data should appear near the top of the results. Then click on the link and navigate below the graph to the Related Resources section. Click the link to the GeoFRED map. You may need to change the units to “Percent change from year ago” and zoom out to see more of the nation. You’ll need to zoom out even further to go beyond the continental U.S. (Sorry, Alaska and Hawaii.)
Suggested by Christian Zimmermann.