Wicksell – Interest and Prices

Why low rates of interest can cause deflation – an insight for today from Wicksell

The aim of the post is to clearly explain why in times of falling interest rates there is often deflation. Further, how does this related to today’s economy. I will explain it in terms of a simple model put forth in the economic theory of Knut Wicksell.

From the great but forgotten Stockholm school of economics

Knut Wicksell was a 19th century Swedish economist who attempted to explain the paradoxical relationship between low-interest rate environments and deflation.  His book, Geldzins und Guterpreise  or in English Interest and Prices, contained the leading theory of price moments which would be developed by the Austrian school into a business cycles and prices movement before Keynes.

Wicksell and the Quantity theory of money

Wicksell maintained that the quantity theory of money (MV=PQ) was still valid in the long-run. However, Wicksell was trying to explain movement in commodity prices distinct from this long-run  assertion. Wicksell  felt that Ricardo’s cash economy was too narrow and understanding of money and purchasing power.

Wicksell’s theoretical lineage comes from a fusion of the theories of the theory of David Ricardo, the Lausanne school – Léon Walras and the early Austrian school specifcally Eugen von Böhm-Bawerk.

Money rate of interest and the natural rate of interest

The theory is simple. There are actually two rates of interest.

One is the bank rate of interest, the money rate of interest or the market lending rate. That is the rate of interest entrepreneurs or must pay on loaned capital. This is clear as it is observable and measurable.

The second rate of interest is the real rate of interest or the natural rate of inerest. The real rate of interest is the marginal productivity of capital. For simplification we can say the profit rate. The profit rate is the rate of return businesses actually get on their capital. This rate will equilibrate the the supply and demand for loanable funds.

Here is the key point: It is the interaction between the bank rate of interest and the natural rate that determines price movements, that is inflation or deflation. This seems so obvious once your read it, but if this is so, why have so many economist tried to use complex verbose theories.

Banks create endogenous money

Wicksell believed banks create purchasing power or endogenous money.  When a bank lends money to an entrepreneur, it literally expands the money supply. The was a key point. This highly elastic credit economy Hayek latter used to  create a theory of credit cycles.

This endogenous creation of money was manifest by the interest rate.

Example of Wicksell’s interest rate theory

Lets say the bank rate of interest is 10%. If the profit rate was 10% the market and prices there would be an equilibrium. However, if the profit rate was only 5% and the bank rate of interest was 10%, people would not start new ventures as there would be no economic incentive (negative economic profit). Further even if the bank rate fell, to 9% then 8% then 7% it would still not be enough to equalizes the supply and demand for money. Therefore, the economy would have deflation. This is an example of why in times of rising rates of interest there is often inflation and falling rates of interest there is often deflation.

The reason is there is only one observed interest rate, the bank rate. The real rate of interest if not directly observable. People draw conclusions based on the bank rate of interest. They say ‘gee the interest rate is so low, there has to be inflation or the economy must pick up’. This is not historically observed.

Further, once this process of price movements is initiated in one direction or another, expectations kick in and there is something called the ‘cumulative process’. That means prices have a life of their own and get out of control in the direction they are moving. This could mean a deflationary spiral.

Wicksell’s cumulative process of price movements

The converse is also true and can cause an inflationary process.

Why is deflation and low interest rates are bad ?

Is deflation bad? No, it allows prices to adjust to their natural level in most cases. However, the reason central bankers do not like deflation is they feel it can suppress demand.

What if the bank rate of interest was zero or close to zero? This was the case in post Civil War America and the Great Depression, there is a point where no matter how far interest rates (the bank rate mind you) falls, deflation continues and the economy is not moving. During the Great Depression deflation was about 10% a year. What is wrong with deflation? The real debt becomes larger. Think about this. Why? Again the real rate of interest is below zero.

In this situation, people do not want to put their money in banks, real asset values go up, investments falls, demand is depressed etc. There are many problems. However, the real problem is this – disequilibrium in the supply and demand for money will cause disequilibrium in the real sector. That is recession or depression.

Knut Wicksell tried to explain this in theory.

An alternative to government control of the money supply

The effect could be, no matter how much the government tried to prime the pump it will not work, because the real rate of interest is stuck below zero. Or at least exacerbated businesses cycles.

What is the solution? One idea was something called free money. Even the name ‘free money’ sounds good does it not? The money supply is regulated by market forces and not government control over the money supply. Just like credit cards are issued by banks, so banks could issue money. If they like banks could back it with real assets or not. The supply and demand of money adjusts quickly and business cycles are averted or tempered.

This has worked in the past, but in our modern economy it is only a libertarian pipe dream. That is our economy is stuck in long-term low gear because of a negative real rate of interest, that does not respond to government action. Take a look around and see if this is the case or not today, that is a long-term sluggish economy, despite low interest rates.

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2 responses to “Wicksell – Interest and Prices”

  1. Adam

    Low rates ?

    0% rates is the cost of money only for investment banks.
    They need not to lend it in to the economy. They simply reinvest it at higher rates around the world taking money of the US economy in the process and re-capitalizing them self with the spread courtesy of the Federal Reserve.

    If and when rates would finally rise as they should to reflect the real cost of money all this cash would flow back in.

    The Fed has simply manipulated rates and transfers money from the responsible to the irresponsible and to big to fail.

    Forcing money to perpetuate malinvestment that would other wise be available is the best way to keep the recession from ending.

    Savers lose income and responsible borrowers lose opportunities.

    There are thousands of good banks in the US that act as banks not casinos. Break up the to big to fail monsters and let banking be banking.

    “End the Fed”

    1. Mark Biernat

      Wicksell’s theory of interest and prices was a theoretical model. I currently am leaning towards ending the Federal Reserve. They have caused or made worse every business cycle since their start. And even worse they result in an unfair reallocation of resources not based on value and productivity, not a reinforcement of the haves at the expense of the have nots. If you look at the Gini coefficient, which is a statistical measure of wealth distribution, the wealthy benefit from Fed action.

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