William Petty came up with a basic concept of GDP to attack landlords against unfair taxation during warfare between the Dutch and the English between 1654 and 1676. Charles Davenantdeveloped the method

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GDP can be determined in three ways, all of which should, theoretically, give the same result. They are the production (or output or value added) approach, the income approach, or the speculated expenditure approach. It is representative of the total output and

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GDP can be contrasted with gross national product (GNP) or, as it is now known, gross national income(GNI). The difference is that GDP defines its scope according to location, while GNI defines

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Within each country GDP is normally measured by a national government statistical agency, as private sector organizations normally do not have access to the information required (especially information on expenditure and production by governments).

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The level of GDP in countries may be compared by converting their value in national currency according to either the current currency exchange

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GDP per capita is often used as an indicator of living standards.
The major advantage of GDP per capita as an indicator of standard of living is that it is measured frequently, widely, and consistently. It is measured frequently in that most countries

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The raw GDP figure as given by the equations above is called the nominal, historical, or current, GDP. When one compares GDP figures

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