National Income: GDP, GNP and NNP
National income is the single most important measuring rod of an economy, and questions built on GDP, GNP, NNP and related concepts appear regularly in ADRE, APSC, Assam Police, SSC, Railway and other examinations. The topic looks numerical, but it is really a test of definitions: once a candidate understands which income is earned where, which tax is added and which depreciation is deducted, almost every question can be answered by applying a simple formula. These notes explain the basic aggregates, the three methods of measurement, the difference between real and nominal income, and the exact points where examiners try to confuse candidates.
What exactly is national income?
National income is the total money value of all final goods and services produced by the normal residents of a country during a financial year, counted once to avoid double counting. The emphasis is on three words. "Final" means intermediate goods, that is goods used up in producing other goods, are excluded. "Normal residents" means citizens and institutions whose centre of economic interest lies within the country, even if they are temporarily abroad. "During a year" fixes the period, usually the financial year from 1 April to 31 March in India. National income is a flow concept, not a stock concept: it measures production over a period, not wealth on a particular date.
GDP and its variants
Gross Domestic Product (GDP) is the market value of all final goods and services produced within the domestic territory of a country in a year, irrespective of who produces them. A Japanese factory operating in India contributes to India's GDP. GDP can be expressed at market price (GDP at MP), which includes indirect taxes and excludes subsidies, or at factor cost (GDP at FC), which is the income actually received by the factors of production. The relation is simple: GDP at factor cost equals GDP at market price minus indirect taxes plus subsidies. GDP is the broadest measure used for international comparison, and India's GDP is now the fifth largest in the world.
GNP and the role of NFIA
Gross National Product (GNP) is GDP plus Net Factor Income from Abroad (NFIA). NFIA is the difference between factor income earned by our normal residents from abroad and factor income earned by foreigners within our country. If Indians working abroad send more income home than foreigners take out of India, NFIA is positive and GNP exceeds GDP. For most of its history India has been a net borrower of capital, and interest and dividend payments to foreign investors have kept India's NFIA negative, so India's GNP has generally been lower than its GDP. GNP is therefore a nationality-based concept, whereas GDP is a territory-based concept, and this distinction is a favourite question.
NNP, factor cost and the meaning of National Income
Net National Product (NNP) is GNP minus depreciation, also called consumption of fixed capital. Machinery and buildings wear out while producing output, and this wear and tear must be deducted to arrive at the true net addition to the nation's output. NNP at market price equals GNP minus depreciation. When we further subtract indirect taxes and add subsidies, we get NNP at factor cost, and this is precisely what economists call National Income. In short: National Income = NNP at factor cost. Per capita income, the most common indicator of living standards, is National Income divided by the total population. Because India's population is large, its per capita income has historically remained far below the world average even though its total GDP is among the largest.
Three methods of measuring national income
National income can be measured in three ways, and in principle all three give the same total. The product or value-added method sums the net value added by every producing unit, avoiding double counting by including only value added at each stage. The income method adds up all factor incomes, namely compensation of employees, rent, interest, profit and mixed income of the self-employed. The expenditure method adds up final expenditure, that is private consumption, government consumption, gross domestic investment and net exports. In India the Central Statistics Office, now part of the National Statistical Office, uses a combination of the income and product methods for different sectors because no single method suits the whole economy.
Real versus nominal GDP and the GDP deflator
Nominal or GDP at current prices uses the prices of the year in question, so it rises partly because of higher output and partly because of higher prices. Real or GDP at constant prices is calculated using the prices of a fixed base year, so it reflects only changes in physical output and is therefore the correct measure of economic growth. The GDP deflator, defined as nominal GDP divided by real GDP multiplied by one hundred, is the broadest measure of the price level in the economy and covers all goods and services, unlike the consumer price index which covers only a fixed basket. India's national accounts are presently built on the base year 2011-12, replacing the earlier base of 2004-05, and the National Statistical Office under the Ministry of Statistics and Programme Implementation releases the estimates.
Key facts at a glance
- GDP: value of final goods and services produced within domestic territory in a year.
- GNP = GDP + Net Factor Income from Abroad (NFIA).
- NNP = GNP minus depreciation (consumption of fixed capital).
- National Income = NNP at factor cost.
- Per capita income = National Income divided by population.
- GDP at FC = GDP at MP minus indirect taxes plus subsidies.
- Three methods: product (value added), income and expenditure.
- Real GDP uses base-year prices; nominal GDP uses current prices.
- GDP deflator = (nominal GDP / real GDP) x 100.
- Base year of India's national accounts: 2011-12.
- Node: National Statistical Office (NSO) under MoSPI.
- First estimate of India's national income: Dadabhai Naoroji, 1868.
- First National Income Committee (1949) chaired by P.C. Mahalanobis.
- First official national income estimate: 1951-52.
Quick revision points
- GDP is territory-based; GNP is nationality-based.
- India's NFIA is generally negative, so GNP is usually below GDP.
- Depreciation is deducted to move from gross to net.
- Indirect taxes are subtracted and subsidies are added to reach factor cost.
- Transfer payments such as pensions and scholarships are not included in national income.
- Intermediate goods and second-hand sales are excluded to prevent double counting.
- Real GDP growth measures actual output growth; nominal growth includes inflation.
How to prepare this topic
- Write the four core formulas (GNP, NNP, NI, per capita income) ten times until they are automatic.
- Practise numerical questions where GDP, NFIA, depreciation, taxes and subsidies are given and one aggregate is asked.
- Learn the three measurement methods with one example each.
- Memorise the base year and the institution that releases the estimates.
- Note the difference between factor cost and market price with a numerical illustration.
- Revise the historical landmarks, especially Dadabhai Naoroji and the 1949 Committee.
Common exam traps
- Confusing GDP with GNP: GDP stays within the border, GNP follows the residents.
- Adding indirect taxes when moving to factor cost instead of subtracting them.
- Forgetting to add subsidies while converting market price to factor cost.
- Treating transfer payments as factor income, which they are not.
- Mixing up real and nominal GDP: real is at constant prices, nominal at current prices.
- Assuming National Income equals NNP at market price; it is NNP at factor cost.
Frequently Asked Questions
What is the difference between GDP and GNP?
GDP measures the value of final goods and services produced within the domestic territory of a country, no matter who produces them. GNP measures the value produced by the normal residents of the country, whether they produce it at home or abroad. GNP equals GDP plus net factor income from abroad, so a country with positive NFIA has a GNP higher than its GDP.
Why is NNP at factor cost called National Income?
NNP is obtained after deducting depreciation from GNP, which gives the net output of the nation. When indirect taxes are removed and subsidies added, the figure represents the total income actually received by the factors of production, that is land, labour, capital and enterprise. This factor-cost figure is the definition of National Income used by economists.
What are the three methods of measuring national income?
The product or value-added method sums net value added by all producing units, the income method sums all factor incomes such as wages, rent, interest and profit, and the expenditure method sums final expenditure on consumption, investment, government spending and net exports. In principle all three yield the same total because every expenditure is someone's income.
What is the difference between real GDP and nominal GDP?
Nominal GDP is measured at current prices and therefore changes when prices change, even if output is unchanged. Real GDP is measured at the prices of a fixed base year and reflects only changes in the quantity of goods and services produced. Real GDP is used to measure economic growth in a meaningful way because it removes the effect of inflation.
Which body releases India's national income estimates and on which base year?
The National Statistical Office, under the Ministry of Statistics and Programme Implementation, releases India's national income estimates. The present series uses 2011-12 as the base year, which replaced the earlier base year of 2004-05, and the estimates are published both at current and constant prices.