I am writing this post for two reasons, the first of which has nothing to do with taxation, and the second of which has nothing to do with visualization. Like peanut butter and chocolate however, they do go well together.
My first reason for this post was to play with the D3.js toolkit for constructing an interactive, animated visualization with real world data; and then see how nicely it would embed in a wordpress post like this one. I have to say that the more I use D3 the more impressed I am. There’s a bit of an adjustment to make if you are used to a more procedural approach to defining graphics (such as QuickDraw or OpenGL), however the data joins and enter/append/exit methods for managing changing data are rather elegant. D3 is certainly another nail in the coffin for Flash, not requiring any client-side install. I look forward to seeing the development of the new authoring tools and libraries that are being built on top of D3.
My second reason for doing this post was to see what the distribution of state and local taxes is across states for different income groups. This data is from the Census Bureau 2008, and is estimated for a family of 4 living in the largest urban center of each state. The taxes included are not just income and property taxes, but also things like vehicle registration and other taxes. What is expected but still striking to see about these data is how consistently higher the taxes are on the upper eastern seaboard at all income levels. In addition, the view clearly shows how lower incomes pay a larger share of income towards these local taxes, as they are not all tied to income level. These data to not factor in federal taxes, however given that most state and local taxes are deductible on the federal tax return, you can see how the federal tax code is in effect is creating a subsidy for the higher taxation states and lower income individuals, relative to the states with lower taxation levels and higher incomes respectively.