Demand for Money: Classical, Quantity (Fishers, Cambridge, Keynesian and Friedman Approaches)
The demand for money refers to how much assets individuals wish to hold in the form of money (as opposed to illiquid physical assets.) It is sometimes referred to as liquidity preference. The demand for money is related to income, interest rates and whether people prefer to hold cash(money) or illiquid assets like money.
Money performs two important functions:
(i) Medium of exchange
(ii) Store of value
It is due to these two functions that money is considered as indispensable by the society. Therefore, demand for money is a derived demand. Demand for money is a very crucial concept as the value of money depends on the demand for money. There are different concepts of the demand for money.
Classical View of Money
The Classical economists viewed that money does not have any inherent utility of its own but is demanded for transaction motive. Money serves as a medium of exchange. Irving Fisher’s version of the quantity theory of money which he developed in his book “Purchasing Power of Money” is the most famous version and represents the Classical approach to the analysis of the relationship between the quantity of money and the price level.
With V and T remaining constant, P changes proportionately to the changes in M, such that if M is doubled, P is also doubled but the value of money is halved.
- It does not explain how a change in M changes P
- P is regarded as a passive factor which is unrealistic
- Not only M determines P but also P determines M.
Quantity Theory of Money
The concept of the quantity theory of money (QTM) began in the 16th century. As gold and silver inflows from the Americas into Europe were being minted into coins, there was a resulting rise in inflation. This development led economist Henry Thornton in 1802 to assume that more money equals more inflation and that an increase in money supply does not necessarily mean an increase in economic output. Here we look at the assumptions and calculations underlying the QTM, as well as its relationship to monetarism and ways the theory has been challenged.
- Quantity Theory of Money Fisher’s Version:
Like the price of a commodity, value of money is determinded by the supply of money and demand for money. In his theory of demand for money, Fisher attached emphasis on the use of money as a medium of exchange. In other words, money is demanded for transaction purposes.
As a truism, in a given time period, total money expenditure is equal to the total value of goods traded in the economy. In other words, national expenditure, i.e., the value of money, must be identically equal to national income or total value of the goods for which money is exchanged, i.e.,
MV = ∑ piqj = PT ….(4.1)
M = total stock of money in an economy;
V = velocity of circulation of money, that is, the number of times a unit of money changes its hand;
Pi = prices of individual goods;
∑P = p1q1 + p2q2 + … + pnqn are the prices and outputs of all individual goods;
qi = quantities of individual goods transacted;
P = average or general price level or index of prices;
T = total volume of goods transacted or index of physical volume of transactions.
This equation is an identity that always holds true: It tells us that the total stock of money used for transactions must equal to the value of goods sold in the economy. In this equation, supply of money consists of nominal quantity of money multiplied by the velocity of circulation.
The average number of times that a unit of money changes its hand is called the velocity of circulation of money. The concept that provides the link between M and P x T is also called the velocity of money. V is, thus, defined as total expenditure, P x T, divided by the amount of money, M, i.e.,
V = P x T/M
2. Quantity Theory of Money: Cambridge Version
An alternative version, known as cash balance version, was developed by a group of Cambridge economists like Pigou, Marshall, Robertson and Keynes in the early 1900s. These economists argue that money acts both as a store of wealth and a medium of exchange. Here, by cash balance and money balance we mean the amount of money that people want to hold rather than savings.
According to Cambridge economists, people wish to hold cash to finance transactions and for security against unforeseen needs. They also suggested that an individual’s demand for cash or money balances is proportional to his income. Obviously, larger the incomes of the individual, greater is the demand for cash or money balances.
Thus, the demand for cash balances is specified by:
Md = kPY …(4.6)
where Y is the physical level of aggregate or national output, P is the average price and k is the proportion of national output or income that people want to hold. Let us assume that the supply of money, MS’ is determined by the monetary authority, i.e.,
MS = M …(4.7)
Equilibrium requires that the supply of money must equal the demand for money, or
k and Y are determined independently of the money supply. With k constant given by the transaction demand for money and Y constant because of full employment, increase or decrease in money supply leads to a proportional
increase and decrease in price level. This conclusion holds for Fisherian version also. Note that Cambridge ‘k’ and Fisherian V are reciprocals of one another, that is, 1/k is the same as V in Fisher’s equation.
The classical relationship between money supply and price level can be illustrated in terms of Fig. 1. This diagram is interesting in the sense that it first establishes the relationship between money supply and national output or national income below the full employment stage (YF). For this relationship, the origin ‘O’ is important.
Now the relationship between money supply and price level after the full employment stage can be established assuming O’ as the origin. Before the attainment of full employment state (YF), an increase in money supply (from OM1 to OM2 and to OYF) causes national income (shown by the steep output curve) to rise more rapidly than the price level.
By utilising its resources efficiently and fully, an economy can increase its output level by increasing the volume of investment consequent upon an increase in money supply. Since there is a limit to output expansion due to full employment (i.e., beyond which output will not increase), an increase in money supply from (M3 to M4) will cause price level to rise from (P3 to P4) proportionally (shown in the upper panel).
For stability in price level money supply should grow in proportion to increases in output.
- Keynesian Quantity theory of Money
Keynes believed that changes in the money supply affect aggregate demand because of the relationship between the rate of interest and planned investment. The link remains on the basis of how today’s Keynesians view the impact of monetary changes on GNP.
The Keynesians’ view of the transmission of changes in the money supply can be stated thus:
An increase in money supply lowers the interest rate. Thus planned investment increases. This causes the aggregate expenditure (C+I+G) schedule to shift up. This addition to aggregate expenditure increases equilibrium GNP by shifting the aggregate derived expenditure (C+I+G) schedule to the right.
- Friedman Quantity Theory of Money
Friedman in his essay, “The Quantity Theory of Money—A Restatement” published in 1956 beautifully restated the old quantity theory of money. In his restatement he says that “money does matter”. For a better understanding and appreciation of Friedman’s modern quantity theory, it is necessary to state the major assumptions and beliefs of Friedman.
First of all Friedman says that his quantity theory is a theory of demand for money and not a theory of output, income or prices.
Secondly, Friedman distinguishes between two types of demand for money. In the first type, money is demanded for transaction purposes. It serves as a medium of exchange. This view of money is the same as the old quantity theory. But in the second type, money is demanded because it is considered as an asset. Money is more basic than the medium of exchange. It is a temporary abode of purchasing power and hence an asset or a part of wealth. Friedman treats the demand for money as a part of the wealth theory.
Thirdly, Friedman treats the demand for money just like the demand for any durable consumer good.
The demand for money depends on three factors:
(a) The total wealth to be held in various forms
(b) The price or return from these various assets and
(c) Tastes and preferences of the asset holders.
Friedman considers five different forms in which wealth can be held, namely, money (M), bonds (B), equities (E), physical non-human goods (G) and human capital (H). In a broad sense, total wealth consists of all types of “income”. By “income” Friedman means “aggregate nominal permanent income” which is the average expected yield from wealth during its life time.
The wealth holders distribute their total wealth among its various forms so as to maximise utility from them. They distribute the assets in such a way that the rate at which they can substitute one form of wealth for another is equal to the rate at which they are willing to do.
Accordingly the cost of holding various assets except human capital can be measured by the rate of interest on various assets and the expected change in their prices. Thus Friedman says there are four factors which determine the demand for money. They are: price level, real income, rate of interest and rate of increase in the price level.
Friedman’s quantity theory of money can be explained diagrammatically in the following figure (fig.2)
In the figure while the X-axis shows the demand and supply of money, Y-axis measures the income level. MD is the demand curve for money which changes along with income. MS is the supply curve for money. These two curves intersect at point E and the equilibrium income level OY is determined. If there is an increase in money supply, the supply curve shifts to M1S1. At this level the supply is greater than demand and a new equilibrium is established at E1. At the new equilibrium level the income increases to OY1.