Explanation:

The National Income of India is estimated by production method alone.
National Income- It also broadly indicates people's standard of living. Income can be measured by Gross National Product (GNP), Gross Domestic Product (GDP), Gross National Income (GNI), Net National Product (NNP) and Net National Income (NNI). In India the Central Statistical Organization has been formulating national income.

These three calculating GDP methods yield the same result because National Product = National Income = National Expenditure.

1. The Product Method:

In this method, all goods and services produced during the year in various industries are added up. This is also known as value-added to GDP or GDP at the sector of origin's cost factor. India includes the following items: agriculture and allied services; mining; development, construction, the supply of electricity, gas, and water, transport, communication, and trade; banking and industrial real estate and property ownership of residential and commercial services and public administration and defence and other services (or government services). It is, in other words, the amount of the added gross value.

2. The Income Method:

In a nation that produces GDP during a year, people earn income from their jobs. Thus the sum of all factor incomes is GDP by revenue method: wages and salaries (employee compensation) + rent + interest + benefit.

3. Expenditure Method:

This approach focuses on products and services generated during one year within the region.

GDP is subtracted from the portion of consumption, investment, and government spending expended on imports. Likewise, all manufactured components, such as raw materials used in the manufacture of products for sale, are also exempt.

Thus GDP by expenditure method at market prices is net export, which can be positive or negative