United States. Bureau of Economic Analysis. "Gross Domestic Product: First Quarter 2015 (Second Estimate) | Corporate Profits: First Quarter 2015 (Preliminary Estimate) : Historical Comparison, BEA 15-21,"
Bureau of Economic Analysis (BEA) News Releases
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https://fraser.stlouisfed.org/title/6148/item/602239/content/pdf/bea_newsreleases_20150529_historical-comparisons, accessed on March 20, 2025.