U.S. Census Bureau. (2005). U.S. Census Bureau, statistical abstract of the United States: 2004-2005. Income, expenditures, and wealth. (Section 13, Table 677, p. 449). Washington, DC: U.S. Census Bureau. Retrieved July 15, 2005, from http://www.census.gov/prod/www/statistical-abstract-2001_2005.html

"This section presents data on gross domestic product (GDP), gross national product (GNP), national and personal income, saving and investment, money income, poverty, and national and personal wealth." "The primary source for data on GDP, GNP, national and personal income, gross saving and investment, and fixed reproducible tangible wealth is the Survey of Current Business, published monthly by the Bureau of Economic Analysis (BEA)."