TaxGraphs

TaxGraphs is a web app that graphs marginal and effective tax rates against income for each US state. Graphs include a comparison between overall state tax rates and a detailed breakdown of each state's tax rate into its individual components. The app currently supports showing graphs for the single and married jointly filing statuses, as well as adjusting income with the standard deduction.

Tax data is collected from each state's official website and the Tax Foundation. The app uses AngularJS and D3.js to display the visualization, and Browserify and LESS for asset compilation.

The app is currently hosted on GitHub Pages and can be visited at http://taxgraphs.io.

Setup

To run the app locally, install Node.js and then execute the following from the project directory:

npm install -g grunt-cli
npm install

Executing grunt will set up grunt-watch to monitor changes and compile the static assets and tax data. It will also host the app locally at localhost:1337 with livereload enabled.

Executing grunt dist will prepare the app for distribution with concatenated and minified assets.

The Grunt tasks and build process originate from the Sails.js new project scaffold.

Data

The tax data is in the data/ folder and is broken down into individual JSON files for federal and each state's tax rates. The json-bake task concatenates all the JSON files together, and a custom Grunt task then preproceses the tax data and minifies the final JSON.

The rate property for each tax can be one of the following types:

• Number: A flat tax rate.
• Array: A set of marginal tax brackets.
• Object: Sets of marginal tax brackets for different filing statuses.

Each marginal tax bracket has the following structure:

[
  Bracket income minimum,
  Bracket marginal tax rate,
  Total tax at the bracket income maximum
]

The following is an example:

"income": {
  "rate": {
    "single": [
      [0, 0.1, 907.5],
      [9075, 0.15, 5081.25],
      [36900, 0.25, 18193.75],
      [89350, 0.28, 45353.75],
      [186350, 0.33, 117541.25],
      [405100, 0.35, 118118.75],
      [406750, 0.396]
    ]
  }
}

The total tax is not available for the last bracket since there is no maximum. The total tax is also not available in any tax bracket for the individual JSON files; it is instead calculated and added to the final JSON file during compilation.

Pull requests to update or correct any of the tax rates are welcome.

License

The data is licensed under the CC BY-NC 4.0 license, while the code for the project is licensed under the MIT license.