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.


The ccc package can be installed with Anaconda via:

conda install -c conda-forge ccc

or with PyPI via:

pip install cost-of-capital-calculator

Web Application#

You can also use Cost-of-Capital-Calculator through a web application, hosted on Compute Studio. The web application is limited in that you cannot consider policy reforms to the individual income tax code, but it is an easy to use alternative to the Python API.


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.

Citing the Cost-of-Capital-Calculator Model#

Cost-of-Capital-Calculator (Version 1.4.1)[Source code], PSLmodels/Cost-of-Capital-Calculator