GDP, gross domestic product at market prices is the final result of the production activity of resident producer units. It can be defined in three ways: as the sum of gross value added of the various institutional sectors or the various industries plus taxes and less subsidies on products; as the sum of final uses of goods and services by resident institutional units (final consumption, gross capital formation, exports minus imports); as the sum of uses in the total economy generation of income account (compensation of employees, taxes on production and imports less subsidies, gross operating surplus and gross mixed income). (ESA 1995 8.89.)
Intermediate consumption consists of the value of the goods and services consumed as inputs by a process of production, excluding fixed assets whose consumption is recorded as consumption of fixed capital. The goods and services may be either transformed or used up by the production process. (ESA 1995 3.69.)
Products used for intermediate consumption should be recorded and valued at the time they enter the process of production. They are to be valued at the purchasers’ prices for similar goods or services at that time. (ESA 1995 3.72.)
Output at basic prices consists of the products which have been produced in the accounting period. Three categories of output are distinguished: market output, output for own final use, and other non-market output. Output is to be recorded and valued when it is generated by the production process. (ESA 1995 3.14.-3.16.)
Value added (gross) refers to the value generated by any unit engaged in a production activity. In market production it is calculated by deducting from the unit's output the intermediates (goods and services) used in the production process and in non-market production by adding up compensation of employees, consumption of fixed capital and possible taxes on production and imports.