United States. Bureau of Economic Analysis. "Gross Domestic Product: Fourth Quarter and Annual 2015 (Third Estimate) | Corporate Profits: Fourth Quarter and Annual 2015, BEA 16-16," Bureau of Economic Analysis (BEA) News Releases (March 25, 2016). https://fraser.stlouisfed.org/title/6148/item/602335, accessed on March 22, 2025.