It can also be calcuated by the sum of value added at every stage of production of all final goods and services.
The most common approach to calculating GDP is by expenditure:
GDP, or Yd = Consumption
+ Government spending
+ (eXports - iMports)
where X - M = Net emports.
Therefore more precisely:
GDP = C + I + G + N
And there are 2 other approaches to calculate GDP:
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