Data collection
Data collection is accomplished through observation and/or by reviewing measures of economic performance, such as unemployment rates, personal income and expenditures, interest rates, business inventories, gross product by industry, and numerous other economic indicators or indices. Such measures of economic performance may be found in secondary sources such as business, trade, government, and general-interest publications. The Bureau of Economic Analysis (BEA), contained in the U.S. Department of Commerce, provides economic information