The quantity theory of money
· Explains that a rise in the money supply leads to excess demand, leading to a rise in prices, inflation. To put it simply, too much money chasing too few goods.
· The quantity theory is a special case of demand pull inflation.
· The Fisher Equation of Exchange provides evidence for the quantity theory of money.
MV = PT
M = money supply
The total amount of money in circulation in the economy at any given time.
V = velocity
The number of times the money circulates around the economy at any given time. V is influenced by methods of payments such as cash, bank overdrafts, credit or debit. Methods of payments are limited therefore V remains constant.
P = price level
T = total transactions
The measure of all the purchases of goods and services in the economy. T remains constant because the theory assumes money is a medium of exchange, not a store of value, therefore people spend quickly any money they receive.
If V and T remain constant, they cancel each other out and thus a M = P. This means that a rise in M will create a rise in P, therefore explaining the theory.
Criticisms
Keynesians generally reject the theory because….
1. There are too many assumptions that the theory relies upon. They don’t believe that people quickly spend any money they receive. Instead, people hold money balances if share prices/bonds are likely to fall for example, thus V and T cannot remain constant.
2. If there is spare capacity in the economy, Keynesians believe that real output and employment will increase, not the price level. However a counter-argument for that would be the Phillips Curve (more on that to come!).
3. If M has increased, the effect it can have on P is limited if V balances out the increase in P. Reflation of the economy can further limit the effect of a rising money supply on the price level.
4. Reverse causation: Inflation causes an increase in the money supply, not the other way round. Cost push inflation occurs and the money supply adapts (by rising) to finance a higher price level set for consumers to pay.