In 2011 a report was published by World Bank in which the Gross Domestic Product (GDP) was about $15094.00 billion. USA GDP was equal to 24.35% of the economy of world. USA GDP steadily went high from 1960 to 2011. GDP gives the measurement of national income and state of the economy of the country.
USA GDP is equivalent to the expense in total for the final goods and services which are produced in the country in a particular time period. So the GDP of USA shows the effects on the economy of the country and mostly it had been stable in the whole period of time.