Over the past 40 years, federal revenues have ranged from nearly 21 percent of GDP, in fiscal year 2000, to less than 16 percent, in fiscal years 2009 through 2012; they have averaged about 18 percent of GDP over the four decades. In addition to projecting the future course of federal revenues, CBO analyzes the budgetary and economic effects of various features of the federal tax system and the effects of potential changes to current tax rules.

Use this menu to filter CBO's publications by topic. From January 2011 forward, all the agency's products are categorized by topic. Cost estimates released prior to the 112th Congress are not categorized by topic.