Census geography: Bridging data from prior years to the 2010 tract boundaries>>Use the LTDB>>

Use the LTDB: Input Your Own Data

The tools described here allow users to input their own data. These tools include a crosswalk file for each year (this is a data file that the program uses to link tract boundaries over time), plus code in Access and STATA that should be used with the crosswalk.

The user must provide an input data file that uses tract boundaries for one of the decades 1970-2000. CAUTION: The format of the tract ID variable in the input data file is critical. It needs to be an 11 character string variable in the form of "SSCCCTTTTTT", where SS = FIPS state, CCC = FIPS county, and TTTTTT = census tract.

We provide an Access database that includes the crosswalk files for every year, as well as a set of simple queries to identify variables in the input file. Users who have Microsoft Access need only to open the database, provide the name of their input file, and respond to queries. Using the "External Data" menu, Access can import a text file, Excel file, or DBF file. No further programming knowledge is required. The Access programming was completed by Zengwang Xu (University of Wisconsin, Milwaukee).

We also provide STATA code. Users who have STATA should also provide an input data file in STATA format. The initial few lines of code need to be completed by the user, listing variable names that STATA will use. The STATA programming was completed by Brian Stults (Florida State University).

The output file from Access (a comma-delimited .txt file) or STATA (a STATA data file) lists all of the 2010 information about the tract from the crosswalk file and values of the input variables converted to 2010 boundaries.

CLICK HERE for the download page that includes the crosswalk and Access/STATA program files.

CLICK HERE for information about the content and use of the crosswalk file.

CLICK HERE for information about the use of the Access and STATA programs.