Introduction:
National income can be measured by the social accounting method. Under this method, the transactions among various sectors such as firms, households, government are recorded and their interrelationships traced.
Firms:
undertake productive activities. They employ factors of production to produce goods and services.
Households:
Households are consuming entities. They represent the factors of production, who receive payment for services rendered by them to firms. (i) Households consume the goods produced by the firms. There is a circular flow of money between these two groups.
Government:
The Government sector refers to the economic transactions of public bodies at all levels-centre, state and local. Their purchases may be financed through taxation, public borrowings. The government provides public health, education. They satisfy the collective wants of society. But Post Offices and railways are separated from the Government sector and included as "Firms".
Rest of the world:
It relates to international economic transactions - income, export, import external loan transaction, and allied overseas investment income and payments.
Capital sector:
(i) Capital sector refers to saving and investment activities. It includes the transactions of banks, insurance corporations, financial houses. These are not included under "Firms".
(ii) The economy is also divided into primary, secondary tertiary and quaternary sectors.
Conclusion:
The social accounting framework is useful for economists as well as policy makers, because it represents the major economic flows and statistical relationships among various sectors of the economic system. It is possible to forecast the trends of economy more accurately.

Introduction:
(i) In India there exists a large unorganized and non-monetised subsistence sector where barter system prevails. So proper valuation of output is very difficult. The difficulties are:
Transfer payments:
(i) Government makes transfer payments like pensions, unemployment allowance, subsidies. They are not included in national income because they are paid without adding anything to the production processes.
Difficulties in assessing depreciation allowance:
(i) High degree of judgement is needed to assess the depreciation allowances and accidental damageś, repair and replacement charges.
Unpaid services:
(ii) Housewife's services like preparation of meals, bringing up children are not directly included in national income. But such services performed by paid servants are included in NI. Rendering services to their friends, painting, singing, also cannot be measured in monetary terms. It is done out of love.
Income from illegal activities:
(i) Income from illegal activities like gambling, smuggling is not included in national income.
(ii) Though these activities have value yet they are not considered as productive from the society point of view.
Production for self - consumption and changing price:
(i) Farmers keep a large portion of food and other goods produced on the farm for self consumption
(ii) The problem is whether that part of the produce which is not sold in the market can be-included in NI or not.
(iii) National income by product method is measured by the value of final goods and services at current market prices. But prices do not remain stable.
Capital Gains:
(i) The problem also arises with regard to capital gains. They must be excluded from NI.
Statistical problems:
(i) There are statistical problems too. Reliable data are not adequate.
(ii) Different languages, customs also create probléms.
(iii) Indians are non-cooperative and indifferent to the official inquiries.
(iv) Statistical staff are untrained and inefficient.
(v) Double counting must be avoided.
Conclusion:
(i) Therefore, national income estimates in our country are not very accurate or adequate. There is at least 10 % percent margin of error.

Introduction:
(i) Whatever is produced is either used for consumption or for saving. So, national output can be computed at any of three levels, ie., production, income and expenditure.
(ii) Therefore there are three methods to measure national income.
Product Method (inventory method):
(i) This method measures the output of the country. Gross value of output from different sectors like agriculture, industry, trade, commerce is obtained by the summation of all the values added in the productive process.
(ii) In India, the gross value of the farm output is obtained as follows:
(iii) Total production of 64 agriculture commodities is estimated. The output of each crop is measured by multiplying the area sown by the average yield per hectare.
(iv) Total output of each commodity is valued at market prices.
(v) The aggregate value of total output of these 64 commodities is taken to measure the gross value of agricultural output.
(vi) The net value of the agricultural output is measured by making deductions for the cost of seed, manures and fertilizers, market charges.
(vii) Net value of each sector is measured in this way.
(viii) Double counting should be avoided.
(ix) Value of output used for self consumption should be counted but sale and purchase of second hand durable goods should be excluded.
Income Method (Factor Earning Method):
(i) National income is calculated by adding up all the incomes generated while producing national product.
(ii) Enterprises are classified into industrial groups.
(iii) Factor incomes are grouped under labour income (wages, salaries, fringe benefits), capital income (profit, interest, dividend) and mixed income (farming, sole proprietorship).
\(\mathrm{Y}=\mathrm{w}+\mathrm{r}+\mathrm{i}+\pi+(\mathrm{R}-\mathrm{P})\)
(iv) Transfer payment, receipt from sale of second hand goods, windfall gains and corporate profit tax must not be included.
(v) Imputed value of rent for self occupied houses or offices and Imputed value of services provided by owners of production units are to be included.
Expenditure method (outlay method):
(i) The total expenditure incurred by the society in a particular year is added together.
(ii) It includes personal consumption expenditure (C), net domestic investment (I), Government expenditure on consumption (G) and net exports (X-M).
\(\mathrm{GNP}=\mathrm{C}+\mathrm{I}+\mathrm{G}+(\mathrm{X}-\mathrm{M})\)
(iii) Expenditure on second hand goods, purchase of shares and bonds, transfer payments and expenditure on intermediate goods should not be included.
Conclusion:
Output = Income = Expenditure
(i) This is because the three methods are circular in nature. So, if the 3 methods are done correctly this equation must hold.

(i) National income is of great importance for the economy of a country.
(ii) National income helps us to know the relative importance and contribution of each sector. We could find how income is produced, how it is distributed, how much is spent, saved or taxed.
(iii) National income data is used to formulate monetary policy, fiscal policy and other policies.
(iv) Data regarding gross income, output, saving and consumption is uscd in economic planning.
(v) National income data is used to build economic models in short run and long run.
(vi) It is used to make international comparison, inter regional comparison and inter temporal comparison of growth of the economy during different periods.
(vii) If income is equally distributed, the per capita income will reflect the economic welfare of the country.