tax-microdata

This repository contains all working files for a project to develop validated input files for use in Tax-Calculator.

For Tax-Calculator results generated when using these TMD input files, see this folder.

The current TMD version is 2.1.1, which was released on May 28, 2026, and is the same as TMD version 2.0.0 except that Tax-Calculator version 6.6.1 (instead of 6.5.3) is used to generate the TMD files.

The current TMD 2.1.1 version differs from the 2.0.0 version only slightly in the national weights (all the WT* columns in the tmd_weights.csv.gz file and just the s006 variable in the tmd.csv.gz file); the non-weights input variables in the tmd.csv.gz file and the contents of tmd_growfactors.csv file are unchanged. When using version 2.1.1 to generate sub-national weights, there will be (presumably small) differences from the sub-national weights generated using version 2.0.0; however, the sub-national weights fingerprints have not yet been updated.

The prior TMD 2.0.0 version included the following significant improvements:

• generate national, state, and Congressional district, input files for 2022: #470 #471 #472 #473 #474
• improve the selection of CPS tax units to represent nonfilers: #438
• vastly improve the reweighting algorithm: #416
• impute values for three variables used in new OBBBA deductions: #397

Usage instructions

If on Windows, it is strongly recommended that you use Microsoft's free Windows Subsystem for Linux to install the free Ubuntu Linux operating system, within which you can download the repository code. If not on Windows, there is nothing to do at this stage.

In order to use the code in this repository, you need to license the 2015 PUF from IRS/SOI. Once you have done that, you will have two CSV-formatted files from IRS/SOI: puf_2015.csv and demographics_2015.csv.

To generate the TMD files from the PUF files, do this:

1. Copy the two 2015 PUF files to the tmd/storage/input folder
2. Install the SIPP files described in tmd/storage/input/SIPP24/README.md
3. Install the CEX files described in tmd/storage/input/CEX23/README.md
4. Run make data in the repository's top-level folder

The make data command creates and tests the three national tmd*csv* data files, which are located in the tmd/storage/output folder. Read this documentation on how to use these three files with Tax-Calculator. Also, you can look at the tests in this repository to see Python code that uses the TMD files with Tax-Calculator.

Sub-national area weights

The repository also produces per-area weight files that adapt the national TMD microdata to a specific state or Congressional district. The records do not change; only the weights do, so that weighted sums and targeted distributional values match state-level (or CD-level) totals from IRS Statistics of Income (SOI) and other published sources.

See tmd/areas/README.md for how to build the weights, what files you get, and how to use them — with or without Tax-Calculator.