Determine the amount of gross income the difference between the cash proceeds received from the sale of goods and material costs of their production.
Aggregate all the value of production for the year production during the year, or all of the value added. In turn value added is the amount added to the total cost of manufactured products at each subsequent production stage. In addition, each production stage is added a certain proportion of equipment depreciation and rental costs.
Calculate the amount of the gross income of the firm per unit of output. It depends on the number of sold results of production (goods) and the prices of each specific product. In this case, the process of formation of gross income for one type of product can be calculated by the formula:

D=ЦxQ where

D — the value of the enterprise's income;
C — price value of the products;
Q — quantity of products sold.
Calculate the sum of all indicators included in gross income: the total income received from the sale of goods, including service and support industries; incomes on securities; income from various (insurance, banking) operations to provide financial services.
Calculate adjusted gross income, which is the amount of gross income, reduced by the amount of value added tax, excise tax and other revenues.
Calculate the gross profit using the formula:

C + lg + G + NX, where

With consumer spending;
lg - the amount of investment of the company;
G - procurement of goods;
NX - net exports.

Thus, listed in this case, the costs amount to GDP and reflect the market valuation of production for the year.