Mahalanobis model

Also called: Nehru-Mahalanobis model, Mahalanobis strategy · Topic: Economic Planning in India: Goals, Models and Import Substitution · NCERT: Class 11, Ch 2 "Indian Economy 1950-1990"

Meaning

The Mahalanobis model is the growth model made by P.C. Mahalanobis for India's Second Five Year Plan (1956–61). It put a large share of public (government) investment into heavy and capital-goods industries, meaning the "machines that make machines", such as steel. The aim was the fastest possible long-run growth. It assumed a mostly closed economy, so India would make its own capital goods at home instead of importing them.

It matters because NCERT says "planning, in the real sense of the term, began with the Second Five Year Plan", and this model shaped that plan. Until the Ninth Plan (1997), Indian planning stayed centred on a big public sector and heavy industry [2].

Explanation

How the model works

• Two-sector model (1953): the model splits the economy into only two parts.
• Capital-goods sector (K-sector): machines, steel and tools, which are used to make other goods.

• Consumer-goods sector (C-sector): food, cloth and other things people use directly.

• The key choice is λk (lambda-k): the share of total investment that goes to the capital-goods sector.

• Core logic, step by step:
• A higher λk means more investment goes into making machines.
• More machines each year let the economy invest more next year.
• Future capacity grows faster, so long-run growth is highest.

• The cost: consumption grows slowly in the early years.

• Four-sector model (1955): this split the consumer side into three parts:

• factory-made consumer goods
• household and small-scale industry (including farming)
• services (such as health and education)
• Planners used it to estimate the jobs and income each sector would create.

Worked example (numbers are only for illustration)

• A country invests ₹100 crore every year.
• Path A: 20% goes to capital goods.
• Few new machines get made, so next year's investment grows only a little.

• More consumer goods are available now.

• Path B: 50% goes to capital goods.

• More machines get made, so next year the country can invest more, and the year after even more.

• After some years, Path B's output overtakes Path A's and keeps growing faster.

• The trade-off: Path B means people consume less today so that the economy can grow faster later.

Where it fits with Harrod-Domar

• The Harrod-Domar model gives only one total growth rate: g = s / v.
• g = growth rate of output
• s = savings rate (the share of income that is saved and invested)
• v = capital-output ratio (ICOR), the capital needed to make one extra unit of output

• Example: if s = 12% and v = 3, then g = 12 ÷ 3 = 4% a year.

• The Harrod-Domar model does not say which sector the investment should go to. Mahalanobis's sector models answered that question [2].

• The Second Plan used both models. Harrod-Domar gave the overall projection, and the Mahalanobis models decided how investment was split between sectors [2]. Both were built on the 1955 Plan-frame.

Key assumptions and division of work

• Closed economy and export pessimism:
• Export pessimism means planners believed India could not earn enough from exports to pay for imported machines.

• So India had to make its own capital goods. This is import substitution (making goods at home in place of buying them from abroad).

• Public sector for heavy industry:

• The state held the "commanding heights", meaning the most important parts of the economy.

• Examples are the steel plants at Bhilai, Durgapur and Rourkela.

• Household and small-scale industry for consumer goods and jobs:

• These units use many workers and few machines.
• So they create more jobs for each rupee invested.

In India

• The plan it shaped: the Second Five Year Plan (1956–61), often called the "Mahalanobis Plan" [2].
• Its focus was fast industrialisation through heavy and basic industries [2].
• Target growth was 4.5% and actual growth was 4.3%, so it was "only moderately successful" [2].

• It gave agriculture lower priority, because the economy was stable when the plan was drawn up [2].

• Policy backing: the Industrial Policy Resolution, 1956 made the "socialistic pattern of society" the goal of economic policy [2].

• Funding and its result:
• The plan depended on large imports paid for with foreign loans [2].
• This led to the foreign-exchange crunch of 1957–58. The "acute shortage of forex" forced planners to cut development targets [2].

• Prices rose by about 30% during the Second Plan, while they had fallen in the First Plan [2].

• Course correction: the Third Plan (1961–66) gave agriculture top priority, because farm output had become the "limiting factor" [2].

• Long legacy: the first eight Plans stayed centred on the public sector and basic industries. From the Ninth Plan (1997), planning moved towards an indicative style, which sets broad goals instead of giving orders [2]. The Planning Commission was replaced by NITI Aayog in 2015, and the last Five Year Plan ended in 2017.
• The man and his institutions: Mahalanobis founded the Indian Statistical Institute (ISI) in 1931. The National Sample Survey (NSS) was set up in 1950 on his advice, when he was Statistical Adviser to the Cabinet [4]. His birthday, 29 June, is observed as Statistics Day [3].

Don't confuse with

• Harrod-Domar model: used for the First Plan (g = s/v). It gives only the total growth rate. The Mahalanobis model decides which sector gets the investment. The Second Plan still used Harrod-Domar for its overall projections [2].
• Vakil-Brahmananda wage-goods model (1956): this was a critique of Mahalanobis. It said wage goods (the food and cloth workers buy with their wages) should come first. Otherwise more jobs lead to more demand for food, food prices rise, and growth slows.
• B.R. Shenoy's dissent: Shenoy was the main dissenter on the Second Plan's panel of economists. He warned against deficit financing (government spending paid for by borrowing or printing money) and heavy state control. He did not build a growth model.
• Export-led growth: this is the opposite strategy. It earns foreign exchange by selling abroad. The Mahalanobis model assumed a closed economy and relied on import substitution.

Prelims Hooks

• The Mahalanobis model has a two-sector version (1953) and a four-sector version (1955), and was built on the 1955 Plan-frame. It was used for the Second Plan (1956–61): target growth 4.5%, actual growth 4.3% [2].
• Trap: the Second Plan did not drop Harrod-Domar. It used Harrod-Domar for the overall growth projection and Mahalanobis for sector allocation [2].
• The key choice in the model is λk, the share of investment that goes to the capital-goods sector. A higher λk means slower consumption now and faster growth later.
• The wage-goods model (1956) came from Vakil and Brahmananda, not from Mahalanobis. The chief warning against deficit financing came from B.R. Shenoy.
• The public-sector steel plants of this strategy were Bhilai, Durgapur and Rourkela. The Industrial Policy Resolution, 1956 set the goal of a "socialistic pattern of society" [2].
• Mahalanobis facts: ISI (1931), journal Sankhya (1933), FRS (1945), National Income Committee (1949), NSS (1950). Statistics Day is 29 June [3], which is different from the UN's World Statistics Day.

Mains Points

• Growth now or growth later (GS-III, growth and inclusion):
• The capital-goods-first strategy gave up early consumption to build long-run capacity. It created India's base in steel, machinery and PSUs.
• But capital-intensive projects (many machines, few workers) created few jobs, and wage goods were neglected.

• Prices rose by about 30% and forex ran short [2]. This supports the Vakil-Brahmananda and Shenoy critiques. NCERT notes that "many economists today reject" the approach, but Mahalanobis played "a vital role in putting India on the road to economic progress".

• Import substitution vs export-led growth:

• Export pessimism led to a closed-economy model.
• The 1957–58 forex crisis [2] showed that even import substitution needs imports, such as machines, and so it needs foreign exchange.

• This lesson helped shape the 1991 reforms and today's push for exports, for example under PLI schemes.

• Agriculture as the binding constraint:

• The move from the Second Plan (low farm priority) to the Third Plan (agriculture at top priority) [2] shows that industry cannot grow for long if food supply lags.
• Use this in answers on agriculture–industry linkages and food security. The data institutions Mahalanobis built, such as the NSS, still form the base of MoSPI data after 75 years [4], which supports arguments for evidence-based policy.

Read more

• Mahalanobis and the Second Plan