We are pleased to announce the release of a new consolidated master index for the U.S.
Census 2010 Summary File 1 (SF1) and American Community Survey (ACS) 5 Year datasets. The
files and documentation are the result of a voluntary effort of Dr. Michael Greenwald
(personal) and Jonathan Brooks (Texas A&M Transportation Institute) and are available
free of charge via the web address below:
What is the challenge the index files address?
The U.S. Census Bureau publishes wonderfully rich data products based on the Decennial
Census and American Community Survey. They also provide high-quality geographic datasets
through the TIGER geography program. SF1, ACS, and TigerLine datasets all have
identification fields; such as FIPS code, LOGRECNO number, or name field. Unfortunately,
no common identification field is available that is capable of linking the three datasets
For example: In Lane County, Oregon the record index value for Census Block Group 1 in
Census Tract 1 is 119370 for 2010 SF1 datasets, but for ACS datasets the same Block Group
is number 4514 (ACS 2006-2010) or 4513 (ACS 2007-2011).
The master index files solve this data interoperability challenge.
How do the index files overcome the data-linking challenge?
The master index files act as an intermediate between TIGER, SF1 and ACS datasets. Each
consolidated index file contains record identifier numbers from 2010 Census SF1, the
2006-2010 ACS, the 2007-2011 ACS, and FIPS location codes for Census Tracts, Census Block
Groups, and even Census Block geographies.
The index files are stored in comma-delimited format and as such are compatible with many
types of software (e.g. Microsoft Excel, Microsoft Access, SAS, SPSS, ArcGIS, etc.). You
can use the same consolidated master index to connect the records from the SF1, the ACS
2006-2010 or the ACS 2007-2010 to their correct Census Tract, Census Block Group or Census
Block! Simply connect your Census datasets to the master index file and then join up to
another dataset. Please note that the index files do not contain any population or
demographic data of any kind; they are simply for linking between disparate datasets. The
normal Census Bureau warnings about comparing SF1 Decennial Census data and ACS sample
data still apply.
There is a consolidated index file for each state, Washington DC, and Puerto Rico. The
files are available as a whole or by state via the website.
Who would find these files useful?
Professionals working with TIGER geographies and population/demographic data from the
Census Bureau may find the master index files to be a useful tool for linking datasets;
* Transportation or Land Use Planners;
* GIS Technicians;
* Public Health Officials;
* Economists; and
Who produced the files? Where can I download/learn more?
The index files and accompanying documentation are the result of a voluntary effort of Dr.
Michael Greenwald (personal) and Jonathan Brooks (Texas A&M Transportation Institute).
Texas A&M Transportation Institute is voluntarily providing a home to the files and is
in no way responsible for the accuracy of or use of the files.
What if I still have questions?
Please contact Dr. Michael J. Greenwald via e-mail
Greenwald will respond as time constraints allow.
Jonathan P. Brooks.
Associate Transportation Researcher
Transit Mobility Program
Texas A&M Transportation Institute
701 N Post Oak Rd, Suite 430
Houston, TX 77063
Tel 713.613.9206 | Cell 806.440.2462