: Data for years 1966 through 2007 were compiled by the National Humanities Alliance, at the request of the Humanities Indicators, from documentation supplied by the National Endowment of the Humanities’ (NEH) Office of Strategic Planning. Data for 2008 to 2015 were provided directly to the Humanities Indicators by NEH’s Office of Planning and Budget. The amount for 2016 was obtained from the agency's Appropriations Request For Fiscal Year 2017
. Funding amounts were adjusted for inflation using the Gross Domestic Product Implicit Price Deflators produced by the U.S. Department of Commerce’s Bureau of Economic Analysis.