GROSS DOMESTIC PRODUCT (GDP)

A region's gross domestic product, or GDP, is one of the ways for measuring the size of its economy. The GDP of a country is defined as the total market value of all final goods and services produced within a country in a given period of time (usually a calendar year). It is also considered the sum of value added at every stage of production (the intermediate stages) of all final goods and services produced within a country in a given period of time. Until the 1992 the term GNP or gross national product was used in the United States. The two terms GDP and GNP are almost identical - and yet entirely different; GDP (or GDI - Gross Domestic Income) being concerned with the region in which income is generated. That is, what is the market value of all the output produced in a nation, the United States, for example, in one year. GDP concerns itself with where the output is produced and not who produced it. Meanwhile, GNP (or GNI - Gross National Income) is a measure of the accrual of income or the value of the output, produced by the "nationals" of a region. GNP concerns itself with who "owns" the production. If we take the USA as an example again, GNP measures the value of output produced by American firms, regardless of where the firms are located. This compares to GDP which is concerned with where the production takes place and not if the company is an American firm or not. Supposing that a firm can be defined as American in an economic world where most large firms are actually global groups.
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the total market value of all final goods and services produced in a country in a given year; equals total consumer, investment and government spending, plus the value of exports minus the value of imports.

A measure of output from U.S. factories and related consumption in the United States. It does not include products made by U.S. companies in foreign markets.

An estimate of the total money value of all the final goods and services produced in a given one-year period using the factors of production located within a particular country's borders.
[See also: Gross National Product (GNP) ]

Gross domestic product is a measure of the total production and consumption of goods and services in the United States. The Bureau of Economic Analysis constructs two complementary measures of GDP, one based on income and one based on expenditures. It is measured on the product side by adding up the labor, capital, and tax costs of producing the output. On the expenditure side, GDP is measured by adding up expenditures by households, businesses, government and net foreign purchases. Theoretically, these two measures should be equal. However, due to problems collecting data, there is often a discrepancy between the two measures. The GDP price deflator is used to convert output measured at current prices into constant-dollar GDP.