The sale and purchase of stocks in the secondary market doesn’t generate any economic activity, these transactions are just transfer of ownership. National Income goes over-estimated by including these transactions in national income computation. The result cannot depict true results; therefore to measure NI such transactions should be excluded.
Government Transfer Payments
Government is an important player of three sector economy and its payments to public without rendering services are considered as non productive payments, theses are known as transfer payments e.g., payment of social security, unemployment allowances, pensions or scholarships to the students. All Such transactions make the NI calculation complicated.
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Private Transfer Payments
In addition to government transfer payments, there are private transfer payments e.g., dowry, charity and pocket money. As these payments are rewarded without any productive service so including such type of nonproductive expenditure in the national income will not give the true picture of NI.
Sale of Used Goods
The trading of second hand commodities like car, TV, or refrigerator cannot be counted for the current year NI as these products were included in the NI when sold first time as new finish goods, there will be duplication if counted again.
Reliable Statistics Availability
National Income measurement is a complicated and delicate process. The availability and processing of data is a sensitive issue, especially in developing countries availability of exact figures are difficult which makes the calculation of accurate NI very complex. In National Income measurement the value of all finish goods from all factors of production is calculated carefully by keeping all the constraints in mind.
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