A variety of methods can be used for calculating national income. The three primary methods used for calculating national income are: 1) output approach 2) income approach and 3) expenditure method. In output method, you can use overall sum of total goods and services produced by the economy to reach to the national income figure. It can be calculated from GDP such as National Income=GDP-Depreciation+ Income form abroad-Indirect taxes. In income approach, output is determined by summing up the total income of the nation which includes amount of money paid to the people in the form of wages such as National Income= National Domestic Product+ Income from abroad. In expenditure approach, income is determined from simple formula i.e. GDP=Consumption+Investment+Government Expenditures+Net Exports (Exports-Imports)