Information Revolution no relation secondary sector of the economy
The three-sector model in economics divides economies into three sectors of activity: extraction of raw materials (primary), manufacturing (secondary), and  service industries which exist to facilitate the transport, distribution and sale of goods produced in the secondary sector (tertiary). The model was developed by Allan Fisher, Colin Clark, and Jean Fourastié in the first half of the 20th century, and is a representation of an industrial economy. It has been criticised as inappropriate as a representation of the economy in the 21st century.According to the three-sector model, the main focus of an economy's activity shifts from the primary, through the secondary and finally to the tertiary sector. Countries with a low per capita income are in an early state of development; the main part of their national income is achieved through production in the primary sector. Countries in a more advanced state of development, with a medium national income, generate their income mostly in the secondary sector. In highly developed countries with a high income, the tertiary sector dominates the total output of the economy.
The rise of the post-industrial economy in which an increasing proportion of economic activity is not directly related to physical goods has led some economists to expand the model by adding a fourth quaternary or fifth quinary sectors, while others have ceased to use the model.Primary sector: 64.5%
Secondary sector: 20%
Tertiary sector: 15.5%This phase represents a society which is scientifically not yet very developed, with a negligible use of machinery. The state of development corresponds to that of European countries in the early Middle Ages, or that of a modern-day developing country.Primary sector: 40%
Secondary sector: 40%
Tertiary sector: 20%More machinery is deployed in the primary sector, which reduces the number of workers needed to produce a given output of food and raw materials. Since the food requirements of a given population do not change much, employment in agriculture declines as a proportion of the population.
As a result, the demand for machinery production in the secondary sector increases and workers move from agriculture to manufacturing.  The transitional way or  phase begins with an event which can be identified with the industrialisation: far-reaching mechanisation (and therefore automation) of manufacture, such as the use of conveyor belts.
The tertiary sector begins to develop, as do the financial sector and the power of the state.Value added, national accounts and the three sector model
The 3 sector model is closely related to the development of national accounts, notably by Colin Clark. The concept of value added is central to national accounting. Value added in the secondary sector of the economy (manufacturing) is equal to the difference between the (wholesale) value of goods produced and the cost of raw materials supplied by the primary sector. Similarly, the value added by the tertiary sector is equal to the difference between the retail price paid by consumers and the wholesale price paid to manufacturers.
The concept of value added is less useful in relation to the quaternary and quinary sectors.See also
Colin Clark (economist)
Jean Fourastié
Primary sector of the economy
Secondary sector of the economy
Tertiary sector of the economy
Quaternary sector of the economy
Information Revolution
De-industrialization
Private sector
no relation