Supplement to What?
In the late 1990's we created the original ZIP Code Resources Page,
containing a variety of information and tools related to ZIP codes. While much of what we talked about in
that document was not time-specific, some of it was. It talked about the status of ZIP codes in the mid-90's and links to data
all refrenced then-current 1990's-vintage resources. Around 2001 we created the updated
Version 2 of the document. References to various
datasets and tools were updated to point to the new post-2000 vintage resources. And now (2012 - 2013), the 2010 census has come and gone and we
are dealing with the 2010 cycle of ZCTA's from the Census Bureau, plus a new way of getting demographic data involving the replacing of
Summary File 3 (decennial census product) with data based on the new American Community Survey (ACS). Rather than create an entire new
Version 3 document we have decided, at least for now, to merely create this supplement (to Version 2). Here we shall deal only with what's
new in the world of ZIP codes in the decade of the 2010's. For general information, or information related specifically to ZIP codes as they
existed in the two earlier decades we refer you to the original pair of documents.
The New 2010 ZCTAs
We first we saw of the 2010 edition of the ZIP Code Tract Areas was in the spring of 2011 with the release of the SF1 (Summary File 1) data
product. As they did in 2000, the Bureau defined the new ZCTA's as an aggregation of the current census blocks. Which are now, of course, 2010 blocks. They updated their ZCTA geography page to reflect the new version. They noted that the experiment with creating the HH and XX pseudo-ZCTAs was dropped for this decade. Probably because they
caused so much confusion among users. Readers of this page (previous link) should focus on the paragraph beginning It is important to note the following: .
New (Post-2010) ZCTA Master Data Set
An important resource created by the MCDC is the master data set where we combine geographic and demographic data regarding ZCTAs. The
version of this data set created to describe the 2000-vintage ZCTAs has been renamed to zcta_master07. We have replaced (i.e. written over with new data) the zcta_master data set so that it now describes the 2010 ZCTAs, and contains demographic indicators taken from the most recently available American Community Survey data. We initially created this new version in 2012, and it used our estimated ZCTA level data allocated from 2006-2010 tract-level period estimates. In August, 2013 we did a major update of the zcta_master and used official 2007-2011 ZCTA-level ACS data for the first time. The data set now contains the current Congressional District codes (113th congress) as well as the updated ("2012") PUMA codes. We also have updated
the various metropolitan area codes: cbsa (Core Based Statistical Area, i.e. Metropolitan Statistical Areas and Micropolitan S.A.s), Metropolitan
Divisions and Combined Statistical Areas (CSAs).
New United States Zip Codes Web Site
We were recently referred to a new web site - http://www.unitedstateszipcodes.org/
which appears to overlap extensively (in terms of content) with our own "All about ZIP code..." pages. But it includes some ZIP lookup and mapping tools that ZIP
code users should find very useful. It also features information about shipping rates between ZIP codes for USPS, FedEx and UPS. It has a
free downloadable database, but it also has one that it sells for $29.95. We have not yet had time to use this site much but it certainly
has the look of a very useful resource.
2010 Decennial Census Data
Summary File 1 contains data tables summarizing the results of the 2010 decennial census survey. (The 2010 census did not include a long form, only a short form.) Data for ZIP codes (or ZCTA's, to be move precides) appear with Summary Level codes of 871 (ZCTA within state) on the individual state files. The national file has summaries for all ZCTA's in the nation and has three summary levels: 860 (complete ZCTA's); 870 (ZCTA's within state - same data as the 871 summaries on the state files but with a different SumLev code just to confuse you); and 880 (ZCTA within county). Since over 90% of all ZCTA's are contained within a single county you mostly get three copies of the same tabular data on the national file. These data can be accessed via the American FactFinder query application at the Census Bureau, or they can be accessed from the Missouri Census Data Center's public data archive using the Uexplore/Dexter query tools. Specifically, go to (sf12010 to access the full tables or
sf12010x to access the much smaller (but often more useful) standard extract data. The latter can also be accessed using our Standard Summary File 1 (2010 Census) Extract Assistant web app. The SF1 Census Profile lets you generate formatted profile reports for up to 4 geographic areas at once, with ZCTA among the levels avialable.
American Community Survey Data
If you are not familiar with the ACS we recommend you see our American Community Survey page for basic background information. Basically, ACS does for 2010 data what SF3 did for 2000 data. Except that it is not simple one-point-in-time data derived from a census, but instead uses survey data collected over a 5-year period (2006-2010 is latest available as of May, 2012).
For some reason the Census Bureau did not tabulate ACS data at the ZCTA level for the 2006-2010 5-year period estimates ACS data released in 2011. We are told we can expect such data to be published when the 2007-2011 data are released near the end of 2012. In the meantime the Missouri Census Data Center has used a census tract-to-ZCTA crosswalk file and 5-year ACS data at the census tract level in order to create estimated 5-year data for ZCTAs for 2006-2010. These data can be accessed in our acs2010 data directory, dataset uszctas5yr -- invoke Dexter to access this dataset here . Note that this is a standard extract dataset. We did not attempt to do complete base tables at the ZCTA level. For that kind of detail we'll need to wait until the Bureau publishes such tables for the next ACS data cycle. Note also that we did not include any estimates of MOE (margin of error) values for these data items. Which is unfortunate because many of the ZCTA's are quite small and that can lead to relative MOE's that are singificantly large (meaning lots of sampling error). If you are looking for basic demographics use the SF1 data. But if you want income or poverty data then this is the best we can do for now. (And for the foreseeable future, for that matter.) Note that the Bureau has opted never to produce any single or 3-year ACS period estimates at the ZCTA level, not even for those ZCTA's with populations of 20,000 or more that would normally qualify.
On December 6, 2012 the Census Bureau published the first official data from the American Community Survey based on
2010 ZCTAs. That data is now accessible from the MCDC public archive in the /pub/data/acs2011 data directory, dataset uszctas:
http://mcdc.missouri.edu/cgi-bin/broker?_PROGRAM=websas.uex2dex.sas&_SERVICE=appdev&path=/pub/data/acs2011&dset=uszctas5yr&view=0 . You can also view these data in a profile format using the MCDC web application at http://mcdc1.missouri.edu/acsprofiles/acsprofilemenu.html.
Just as we have 3 versions of ZIP Code Resources documents for three decades we now have three versions of the MABLE/Geocorr geographic correspondence engine for the same three decades. The new 2012 version is at http://mcdc.missouri.edu/websas/geocorr12.html. You can use this to relate the new codes to all the others such as counties, metro areas, urban/rural, PUMAs (both old and new), 2010 census tracts, congressional districts, etc. (This 2012 version of MABLE/Geocorr replaces the interim 2010 version which is no longer supported).
Correlation List Files Relate ZIP Codes to Common Geographies
The previous paragraph describes the MABLE/Geocorr12 tool which you can use to generate "correlation lists" -
files that define the correlation of one type of geography (such as ZCTAs) to another. We have used this tool
to create a directory of commonly requested equivalencies where the "Source" gecode is the 2010 ZCTA and the
target geographies vary for each file in the directory. You can access this collection at
Initially we have stored files relating 2010 ZCTAs to
We could have gone on and generated many more such files. But instead what we did was provide you with a file,
geocorr12_queryform.html, which you can use to rather easily generate your own. Just browse this form and modify the selection of the Target geocodes before hitting a Run Request button to generate
a national file. Or, if all you care about is one state, you can modify the default selecting of all the states and generate a file that is just what you need. It is very easy, for example, to generate a ZCTA to Congressional District file just for Missouri. Or for Texas, or Tennessee, etc.
- metro areas (aka CBSAs) (2 files: 1 uses 2012-vintage defns and the other 2013 vintage)
- PUMAs (both 2000 and "2012")
- Urban/Rural (what portion of the ZCTA's population live in areas classified as Urban vs.
Rural, using the latest definition based on results of the 2010 census).
- Congressional District (113th congress)
New Resource Relates ZIP Codes to ZCTAs
We sometimes like to think of ZIP codes and ZCTA's as more or less the same thing, the only difference being that ZCTA's are "rounded off" to census blocks while real ZIP codes are not. That is more or less true when talking about standard residential ZIP codes. But there are others; ZIP codes that are neither "standard" nor residential. The ZIP code for Reader"s Digest, for the North Pole (Santa Claus), for the University of Missouri, for Camp Pendleton, for Google headquarters, etc.
These are the special (aka "special", "unique", etc.) ZIP codes that are important to the post office and to the entities that use them to receive their mail. But they do are not spatial areas (they are points in most cases) and people do not live in them. Take ZIP 65211, for example. This code is assigned to the University of Missouri in Columbia, MO. If you want to send me a package here at my office it will be expedited if you use the 65211 ZIP code.
You can also used ZIP 65201 and the folks at the post office will know to put it in the 65211 cubbyhole because they just know where it is. If there were no 65211 then 65201 is the residential ZIP code where the campus is located so that it is what would be used.
A new dataset stored in our public archive provides a crosswalk between all (or at least mostly all) current ZIP codes and the ZCTA's to which they correspond. For standard residential ZIP codes it's simple; they are the same codes. For ZIP code 65211 the ZCTA is 65201. You can either access the original downloaded csv file or you can use Dexter to access the converted dataset (zip_2_zcta10) .