Using data from taxfoundation.org and other sources, this package provides a few tools to inspect historical US income tax brackets and standard deductions. The initial goal of this package was the following rough visualizations. The code and data were put together into a Julia package to show how the plots were produced. There may be errors; use with caution!

The first graph shows the 2023 income tax brackets, the effective tax rate implied by those brackets without any deductions, the effective tax rate with the standard deduction, and finally the effective rate from Taxsim. All data are for the filing status "married filing jointly", other filing statuses are similar. Taxsim includes the Earned income tax credit (EITC) which the other curves do not; this is the reason for the difference between the Taxsim curve and the "tax w deduction from taxFoo.jl" curve. Taxsim includes many other taxes other than the basic income tax brackets and deductions (for example FICA taxes), but does not provide data earlier than 1960. Taxsim is a wonderful tool which we we will continue comparing with and working to understand, but we will not refer to it in the rest of this README.

The next figure shows an animation of US income tax from 1862 to 2024, with all incomes converted into 2024 dollars using CPI data from the Minneapolis Fed.

In the next figure (below) the tax for a few specific years (40-year increments from 1864 to 2024) is shown. We see the low tax in the 1860s, no income tax of 1904, the high wartime tax of 1944, the tax in the middle of the Reagan years (before his final tax cuts), and finally the rates for tax year 2024.

All the figures above assume a "Married filing Jointly" status.