Prompted by Warren Buffett’s appeal to establish a minimum tax on the wealthy and the “fiscal cliff” negotiations in Congress, Ritchie King designed an interactive chart showing historical effective federal tax rates (federal taxes paid divided by taxable income) based on inflation-adjusted 2012 income. This chart shows the 1963 equivalent income and federal tax rate for a married couple filing jointly and earning 100,000 in 2012. Click here for the full interactive visualization.Using Tax Foundation data, King designed the interactive to show equivalent income and federal tax rates for any year from 1913 (when the current US federal tax program