UPSC MainsECONOMICS-PAPER-I202115 Marks
Q10.

Apply the theory of liquidity preference to explain why an increase in money supply lowers the interest rate. What does this explanation assume about the price level?

How to Approach

This question requires a detailed explanation of Keynes’s Liquidity Preference Theory and its implications for interest rate determination. The answer should begin by defining the theory and its core components – the demand for money and the supply of money. It should then explain how an increase in money supply affects the equilibrium interest rate, linking it to the three motives for holding money (transactions, precautionary, and speculative). Finally, the answer must explicitly state the underlying assumption about the price level for this mechanism to hold true. A clear, logical structure with illustrative examples will be crucial.

Model Answer

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Introduction

John Maynard Keynes’s Liquidity Preference Theory, developed in his seminal work *The General Theory of Employment, Interest and Money* (1936), provides a framework for understanding the determination of interest rates in the short run. Unlike classical economists who believed interest rates were determined by the supply and demand for capital, Keynes argued that interest rates are determined by the supply and demand for money. This theory posits that individuals prefer to hold their wealth in the most liquid form – money – and the rate of interest is the ‘reward’ for parting with this liquidity. Understanding this theory is crucial for analyzing the impact of monetary policy on the economy.

The Theory of Liquidity Preference

The Liquidity Preference Theory centers around the idea that the interest rate adjusts to balance the supply and demand for money. The demand for money, according to Keynes, arises from three primary motives:

  • Transactions Motive: Individuals and firms need money to carry out everyday transactions. This demand is positively related to the level of income.
  • Precautionary Motive: People hold money as a buffer against unforeseen expenses or opportunities. This demand is also positively related to income and uncertainty.
  • Speculative Motive: This is the most crucial motive for Keynes. Individuals hold money if they expect interest rates to rise (and bond prices to fall). If they anticipate a fall in interest rates (and a rise in bond prices), they will prefer to hold bonds.

Supply of Money

The supply of money is assumed to be exogenously determined by the central bank (e.g., the Reserve Bank of India). It is represented as a vertical line on a graph, indicating that the quantity of money available is independent of the interest rate.

How an Increase in Money Supply Lowers Interest Rates

When the central bank increases the money supply, the money supply curve shifts to the right. With the demand for money remaining constant (at least initially), this increase in the supply of money creates an excess supply of money in the market. To get rid of this excess money, individuals and firms will attempt to invest it in financial assets, primarily bonds.

This increased demand for bonds drives up their prices. Since the interest rate is inversely related to bond prices, the increase in bond prices leads to a fall in the interest rate. This process continues until the money market reaches a new equilibrium where the quantity of money demanded equals the quantity of money supplied at the new, lower interest rate.

Graphical Representation

Imagine a graph with the interest rate on the y-axis and the quantity of money on the x-axis. The demand for money is a downward-sloping curve, and the supply of money is a vertical line. An increase in the money supply shifts the supply curve to the right, leading to a lower equilibrium interest rate.

The Assumption about the Price Level

The explanation above crucially assumes that the price level remains constant. This is because the theory operates under the assumption of a short-run analysis where prices are ‘sticky’ and do not adjust immediately to changes in the money supply. If the price level were to rise as a result of the increased money supply (inflation), the real value of money would decrease, potentially offsetting the impact on interest rates. In other words, if prices rise proportionally to the increase in the money supply, the real interest rate (nominal interest rate adjusted for inflation) may not fall, or may fall by a smaller amount. The theory assumes a stable price level to isolate the impact of monetary policy on nominal interest rates.

Real-World Example: Quantitative Easing

The implementation of Quantitative Easing (QE) by central banks like the US Federal Reserve and the Bank of England following the 2008 financial crisis provides a real-world example. These policies involved injecting liquidity into the financial system by purchasing government bonds and other assets. The aim was to lower long-term interest rates and stimulate economic activity. While the effectiveness of QE is debated, the underlying principle aligns with the Liquidity Preference Theory – increasing the money supply to lower interest rates.

Conclusion

In conclusion, the Liquidity Preference Theory provides a compelling explanation for how an increase in the money supply can lead to a decrease in interest rates. This mechanism relies on the interplay between the supply and demand for money, driven by the transactions, precautionary, and speculative motives. However, it’s vital to remember that this explanation hinges on the crucial assumption of a constant price level, representing a short-run analysis. Understanding this theory is fundamental to comprehending the impact of monetary policy and its role in managing economic fluctuations.

Answer Length

This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.

Additional Resources

Key Definitions

Nominal Interest Rate
The stated interest rate on a loan or investment, without taking inflation into account.
Liquidity Trap
A situation in which monetary policy becomes ineffective because interest rates are already near zero, and further injections of liquidity do not stimulate economic activity.

Key Statistics

In 2023, the Reserve Bank of India (RBI) conducted multiple liquidity injections through various tools, including repo rate cuts and open market operations, to manage liquidity in the banking system.

Source: RBI Annual Report 2022-23

India's broad money supply (M3) grew by 12.6% in November 2023, indicating a significant increase in liquidity in the economy.

Source: RBI Statistical Tables Relating to Money Supply, Credit and Deposits (as of November 2023)

Examples

Impact of Repo Rate Changes

When the RBI lowers the repo rate (the rate at which it lends money to commercial banks), banks can borrow money at a lower cost. This encourages them to lend more to businesses and individuals, lowering overall interest rates in the economy.

Frequently Asked Questions

What happens if the demand for money is perfectly inelastic?

If the demand for money is perfectly inelastic, an increase in the money supply will lead to inflation rather than a fall in interest rates, as people will simply hold the extra money without investing it.

Topics Covered

EconomicsMacroeconomicsMonetary PolicyMoney SupplyInterest RatesLiquidity Trap