MCDC News and Updates

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Missouri’s Changing Legislative Boundaries

This month, our partners at the Missouri Spatial Data Information Service (MSDIS) present a set of “swipe maps” showing how the Missouri House and Senate district boundaries changed after the 2020 US Census.

The red outlines on each map (the left side of the swipe tool, in this case) indicate the new, post-2020 districts, and the blue outlines represent the previous boundaries. Clicking on any district will show the district number and, for the newer boundaries, the current office holder.

Missouri Census Data Center frequently works with MSDIS on mapping and data projects. MSDIS is a spatial data retrieval and archival system offering many mapping resources, primarily focused on the state of Missouri.

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County-to-County Migration in Missouri

This month’s story map, created by Morgan Hurt of the Missouri Spatial Data Information Service, examines recent inward and outward migration to and from Missouri counties.

The data comes from the 2015-2019 American Community Survey — specifically, county-to-county migration flows, a special tabulation created by the ACS program. This data is not released every year, which is why we don’t yet have this migration data from the newest ACS data release (2017-2021).

Missouri Census Data Center frequently works with MSDIS on mapping and data projects. MSDIS is a spatial data retrieval and archival system offering many mapping resources, primarily focused on the state of Missouri.

Urban/Rural Categories now available in Geocorr 2022

We’ve added the new urban areas to the Geocorr 2022 application this month.

There are two new options in Geocorr for source or target geographies. Urban areas are the complete areas with Census Bureau codes; for example, the Columbia, MO urban area with UA code 18937. Urban/rural portion uses a binary designation (“U” or “R”) for each block to calculate the fraction of urban and rural population for any other geography.

There are significant changes to the urban/rural classifications for the 2020 Census. One major change is that we no longer have two different types of urban area. Previously, there were urbanized areas and urban clusters (collective called urban areas), but now there are only urban areas of a single type. In addition, the method for defining these areas is much more complex than before. The short version of the new definition, from the Bureau’s Urban and Rural page, is:

For the 2020 Census, an urban area will comprise a densely settled core of census blocks that meet minimum housing unit density and/or population density requirements.  This includes adjacent territory containing non-residential urban land uses.  To qualify as an urban area, the territory identified according to criteria must encompass at least 2,000 housing units or a population of at least 5,000.

Among other factors, the longer definition includes:

  • Initial criteria for blocks: >= 425 dwelling units/ square mile, or substantial impervious surface >= 20%, or group quarters facility and >= 500 population/square mile.
  • Candidate blocks are then assembled into urban areas:
    • Start with an initial contiguous core area with >= 500 dwelling units.
    • Add nearby noncontiguous urban blocks: any number of “hops” <= 0.5 mile over land area, and up to one “jump” of 0.51 – 1.5 miles over land area.
  • Combined urban area must have at least 5,000 population or at least 2,000 housing units.
  • Enclaves or surrounded areas are added (or removed), and additional qualifying criteria (airports, indentations, high-employment areas, impervious areas) are applied.

For a complete list of elements comprising the new definition, refer to the Federal Register Notice. See also this helpful PDF, Differences between the Final 2020 Census Urban Area Criteria and the 2010 Census Urban Area Criteria, for more information about the changes.

Please report any errors to Glenn Rice (

More Geographies Added to Geocorr 2022

New in the Geocorr 2022 application this month:

We’ve added current American Indian / Alaska Native / Native Hawaiian areas. These areas include American Indian reservations (state and federal), off-reservation trust lands, Hawaiian home lands (HHLs), joint-use areas, Oklahoma tribal statistical areas (OTSAs), Alaska native village statistical areas (ANVSAs), state designated tribal statistical areas (SDTSAs), and tribal designated statistical areas (TDSAs). Alaska Native Regional Corporations [ANRCs] and tribal subdivisions are not included in MABLE/Geocorr.

The Bureau released block equivalency files for 118th congressional districts and 2022 state legislative districts this month — two months early! — so we’ve replaced the “provisional” CD/SLDs with these new “official” ones.

The next major addition to Geocorr will be the new urban/rural classifications, expected December 2022 or January 2023. There are significant changes to the urban/rural classifications for the 2020 Census — we’ll post more about that later, but if you’re interested, the Bureau’s Urban and Rural page has more detail.

Please report any errors to Glenn Rice (

Geocorr 2022: Now With 2020 (and 2010) PUMAs

We’ve added several new geography types to the Geocorr 2022 application. The new 2020-vintage PUMAs (public use microsample area), released just a few weeks ago, are now available. By request, we’ve also restored the 2010-vintage PUMAs to facilitate crosswalks.

Because the new PUMAs are based on the 2020 census but were released in 2022, we’re interchangeably calling them 2020 and 2022 PUMAs. (This is the same way we handled the 2010/2012 PUMAs.)

For more information about PUMAs, please refer to our “All about PUMAs” page (now due for a revision!) or the Census Bureau’s PUMA reference.

As usual, please report any errors to Glenn Rice (

Post-Redistricting Geographies Now Available in Geocorr 2022

Geocorr 2022 just got better!

Many of our users have been asking when the new, post-Census-2020 Congressional districts would be available in Geocorr. The short answer is that 118th CDs are now included in Geocorr 2022, along with current state legislative districts.

A somewhat longer answer is that the U.S. Census Bureau has not yet released shapefiles or block lists for building 118th CDs or current SLDLs or SLDUs from 2020 tabulation blocks — and is not planning to do so for several months yet.

The Bureau’s Redistricting Data Office (RDO) intends to publish block equivalency files for the 118th Congress and for the 2022 state legislative districts, but not until December of 2022 at the earliest. And, the Bureau’s Geography division will not be releasing block allocation files for the same areas at all. However, the new areas will be published as shapefiles in the cartographic boundary files collection around April or May of 2023. They may also be released with the 2022 TIGER/Line shapefiles, generally around October.

Because of this lack of availability, we obtained new CD and state legislative boundary shapefiles from The American Redistricting Project, merged them, and ran intersections against 2020 TIGER/Line block shapefiles to determine how every block fits into the new districts. This was a tedious process, especially since the block and district shapefiles didn’t line up exactly, but we now have enough data to use for correlations.

With all that said, the new legislative geographies in Geocorr 2022 should be considered provisional until such time as they can be verified via official Census Bureau block equivalency files or shapefiles.

Of lesser interest (mainly for our Missouri users), Geocorr 2022 now also includes the most recent MO library districts.

As always, please contact Glenn Rice ( with technical questions.

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Missouri Median Income vs. Gas Prices

This month’s story map examines trends in Missouri median household income in comparison to gas prices. Data about Missouri income comes from the 2016-2020 American Community Survey via the Missouri Census Data Center, and energy costs data are based off the Consumer Price Index from the United States Bureau of Labor Statistics. County-level gas prices have been taken from the AAA Missouri Gas Prices site, which updates each day.

Missouri Census Data Center frequently works with MSDIS on mapping and data projects. MSDIS is a spatial data retrieval and archival system offering many mapping resources, primarily focused on the state of Missouri.

Data Updates (June 2022)

We have a handful of data updates to report this spring.

In addition, for the convenience of our GIS users, we’ve added national shapefiles for the 2022-vintage congressional districts (118th Congress) and state upper- and lower-chamber legislative districts. These were compiled from individual state shapefiles downloaded from the American Redistricting Project. We have attempted to clean and normalize the attribute tables. Please note that these are not official Census Bureau shapefiles.

Please contact the MCDC website manager with any questions or comments.

The MCDC Listserv is Back in Operation

Long-time users of this site who have subscribed to our email list (listserv) may be interested to know that the list is working again. For several months the old list was broken due to software changes. We’ve migrated all previous users to the new list. The address for subscriptions has changed. The new instructions are:

To subscribe, address an email message to In the body of the message (not the subject), type:

subscribe MCDC-L [your first name] [your last name]

Shortly after sending this message, you will receive a subscription confirmation and instructions on how to post your messages to the list or change your subscriber status.