IRS Migration Data & Profiles
Missouri Census Data Center
Track Migration Via Tax Returns
IRS matches households across
consecutive tax years
Able to determine if a return that came
from County A in year N comes from a
different county the following year.
If 500 returns filed from LA County, CA in
2004 are matched to returns in 2005 from
Clark co, NV in 2005 – what does it mean?
IRS has produced their county-to-county
summary files for years.
These are used by the FSCPE as a key
input for the migration portion of the
annual county estimates.
Files are not freely available; IRS uses
them as a cash cow.
Charlotte Observer Creates online Access
Displayed Maps and Tables Like This
Inspired by the
Charlotte Observer site…
We (Missouri Census Data Center)
contacted the IRS and placed our order for
data back to 1999/2000 and thru
Paid several hundred $. Received a cd-
rom with lots and lots of Excel files.
Two xls files per county: 1 for in-movers
and 1 for out-movers.
We Converted the xls Files
Access the resulting data collection at
Original data in csv format saved here
as well as the xls files -- for Mo only.
Usinmig9900 thru usinmig0506 are
the huge datasets with inmigration.
Corresponding usoutmig datasets
have out-migration data.
Datasets are Nice But Reports…
Are what everybody wants. So we needed
to create an application that would turn the
raw data into something users could easily
access and interpret.
We created a profile application that
displayed all relevant data for a single
county – the “IRS Migration Profile”.
Report title identifies the county; subtitle
indicates the years.
Each line of report summarizes implied
migration “flows” both into and out of the
The “Migration Flow Area” can be another
county or some larger total (such as total
or total domestic).
The LA Migration Profile Tells Us…
Under “Migration Into…/ # Returns” in first
row we find 100,584 . This is the total # of
tax returns filed in LA county in 2005 that
were NOT linked to a return in that county
in 2004. So this is a proxy for in-migration
at the HH level.
The 165,767 # Exemptions figure is just
the total exemptions reported on those
$23,179 was the median (middle) gross
income fig for those 100,584 returns.
Migration Out of Los Angeles CA
These 4 items (rightmost columns of
profile) track “out-migration”.
Based on returns filed in LA county in
2004 that were found in a different county
or country in 2005.
It does not include people who did not file
in 2005 (such as people who died).
About the Report
Only migration flows of 10 or more are
reported on the IRS files and hence in
A parm can be specified to raise this
threshold. I.e. you can specify you only
want to see data for areas where there at
least 40 total flows.
Gross flows = #Returns Into + #Returns
The report is sorted by descending Gross
Generating a Report
Access the main menu page at
To locate this URL go to the Missouri Census Data
Center home page and do a search on “IRS profile”;
follow the “What’s New” link.
Select a state first. Then on the application page
choose the county, the year(s) and, if needed, a
Click the Generate Report button.
Profiles/ is an alternate URL.
If you fail to choose a county you will get a report
showing state totals only – not very interesting.
You can also find a link to these reports using our
applinks interface; the URL is of the form:
Where <ss> is the 2-digits fips state code and
<ccc> is the fips county code. The irsmig_profile
entry will be the last on the resulting menu page.
The latest year of data (based on tax years
2005 & 2006) did not have any data on
gross income. Not sure if gone forever.
IRS was reluctant to sell us the 05/06 data
(because we were putting it on the web.)
See article by Emily Groos, IRS, at