Evaluates the effect of US federal taxes on businesses' investment incentives

Project Overview

Cost-of-Capital-Calculator is a model that can be used to evaluate the effect of US federal taxes on the investment incentives of corporate and non-corporate businesses. Specifically, Cost-of-Capital-Calculator uses data on the business assets and financial policy, as well as microdata on individual tax filers, to compute marginal effective tax rates on new investments. In modeling the effects of changes to the individual income tax code, Cost-of-Capital-Calculator works with Tax-Calculator, another open source model of US federal tax policy. Cost-of-Capital-Calculator is written in Python, an interpreted language that can execute on Windows, Mac, or Linux.



Cost-of-Capital-Calculator (Version 0.1.5)[Source code], https://github.com/open-source-economics/Cost-of-Capital-Calculator



CC0 1.0 Universal (CC0 1.0) Public Domain Dedication


User Documentation



Results will change as the underlying models improve. A fundamental reason for adopting open source methods in this project is so that people from all backgrounds can contribute to the models that our society uses to assess economic policy; when community-contributed improvements are incorporated, the model will produce different results.


Core Maintainers

Contributor Guide

There are two common ways to get started with Cost-of-Capital-Calculator:

The first way to use Cost-of-Capital-Calculator is to download the source code and install the model on your machine. To do this, follow the following instructions:

The CSV output files can be compared to the ./run_examples/*_expected.csv files that are checked into the repository to confirm that you are generating the expected output. If you run into errors running the example script, please open a new issue in the Cost-of-Capital-Calculator repo with a description of the issue and any relevant tracebacks you receive.

The second way to use Cost-of-Capital-Calculator is through a web application, Cost of Capital Calculator. This way allows you to generate estimates of marginal effective tax rates and the cost of capital across production industries, type of asset, and separately for corporate and non-corporate entites and different forms of financing. The web application is limited in that you cannot consider policy reforms to the individual income tax code.

Of course, you can get started with Cost-of-Capital-Calculator both ways.


Unit Tests


Integration Tests


Link to webapp


Public Issue Tracker


Public Q & A