Compounding

Imagine that Jesus’ mother had put a small gold coin weighing 3 grammes in Jesus’ retirement account at 4% interest just after he was born in the year 1 AD. Jesus never retired but he promised to return. Suppose now that the account was kept for this eventuality. Imagine now that the end is near, and that Jesus is about to return. How much gold would there be in the account in 2018?

It is an amount of gold weighing 11 million times the mass of the Earth. The yearly interest would be a gold nugget weighing 440,000 times the mass of the Earth. There is a small problem, a fly in the ointment so to say. It would be impossible to pay out Jesus because there simply isn’t enough gold.

It might seem that the bank had to close long ago because of a lack of gold, but that isn’t true. As long as Jesus doesn’t show up it can remain open, at least if the borrowers are allowed to borrow more to pay for the interest. If the economy grows 4% it may not be such a big deal. The interest can be created out of thin air by making new loans that allow borrowers to pay for the interest. And if Jesus doesn’t claim his gold when he returns and accepts bank credit, everything will be fine.

There is a limited amount of gold while compound interest is infinite. As long as bankers can create money out of thin air to pay for the interest and people accept bank deposits for payment, everything is fine. Problems only arise when people demand real gold. A bank can go bankrupt when depositors want to take out their deposits in gold.

Central banks

Perhaps Jesus’ retirement account isn’t such a big problem after all. Our money isn’t gold but currencies central banks can print. Assume now that Jesus’ mother had put one euro in the account instead. One euro at 4% interest makes 22,000,000,000,000,000,000,000,000,000,000,000 euro after 2017 years. That may seem an intimidating figure, but the European Central Bank can take 22 pieces of paper and print 1,000,000,000,000,000,000,000,000,000,000,000 euro on each of them. And there you are. Something like this happened during the financial crisis of 2008. This is called quantitative easing. You may have heard that word before.

Central banks can print new dollars and euros to cope with a shortfall. In fact, this is what central banks often do. There is always a shortfall because of interest because most money is debt and interest on this debt needs to be paid. To make up for the shortfall, there are two options. First, people can borrow more. Second, central banks can print new currency. Both things can happen at the same time. Central bank decisions about interest rates are also about dealing with the shortfall caused by interest charges.

When central banks lower interest rates, people can borrow more because interest rates are lower. Central banks lower interest rates when people are borrowing less than is needed to cope with the shortfall. If central banks raise interest rates, people can borrow less because interest rates are higher. Central banks raise interest rates when people are borrowing more than is needed to cope with the shortfall and the extra money makes people want to buy more stuff than can be made. And if people don’t borrow at all, this is a crisis, and central banks may print more currency to cope with the shortfall.

Interest on capital versus economic growth

There is a problem central banks can’t fix by printing more currency. Interest is more than just interest on money. Interest is any return on investment. Throughout history returns on investments were mostly higher than the rate of economic growth. Most of these returns have been reinvested so a growing share of total income was for investors. This can’t go on forever because who is going to buy the stuff corporations make in order to keep these investments profitable? A simple example can illuminate that.

The graph above shows how total income and interest income (in red) develop with an economic growth rate of 2% and an interest rate of 5% when interest income starts out as 10% of total income and all interest income is reinvested. After 25 years the economic pie has grown faster than interest income and wages have risen. At some point interest income starts to rise faster than total income, and wages go down. After 80 years there’s nothing left for wages. This graph explains a lot about what is going on in reality.

In the short run it was possible to prop up business profits and interest rates by letting people go further into debt to buy more stuff. In the long run, the growth rate of capital income cannot exceed the rate of economic growth. Interest rates depend on the returns on capital so this can explain why interest rates went down in recent years. In the past interest rates below zero weren’t possible but from time to time there were economic crises and wars that destroyed a lot of capital. This created new room for growth.

Wealth inequality and income inequality

When interest rates go down, the value of investments tend to rise. If savings yield little this benefits the wealthy as most people have their money in savings while the wealthy own most investments. But it is important to know the cause otherwise you might think that interest rates should rise. The graph above shows that wealth inequality causes interest rates to go lower, hence redistributing income, for example via higher wages or taxes on the wealthy, can bring higher interest rates.

There is a difference between wealth inequality and income inequality. Your labour income and the returns on your investments are your income. If you are rich but make no money on your investments, your wealth doesn’t contribute to your income. In reality wealthy people make better returns on their investments than others because they have better information and can take more risk. Still, the graph shows that income and wealth inequality can’t increase indefinitely, and that returns on investments can’t exceed the reate of economic growth in the long run, hence interest rates need to go lower.

Most people pay more interest than they receive. The interest paid on mortgages and loans is the proverbial tip of the iceberg. Interest is hidden in rents, in taxes because governments pay interest on their debts, and the price of every product and service because investments have to be made to make these products and services. German research has shown that 80% of the people pay more in interest than they receive, while only the top 10% of richest people receive more in interest than they pay. Lower interest rates benefit most people despite some side-effects that work in the opposite direction.

Economic cycles

Humans are herd animals. They buy stuff and even go into debt to buy stuff when others are going into debt to buy stuff too. Suddenly they may realise that they have bought too much or have gone too deeply into debt, and all at the same time. One day they may be borrowing money, queueing up before the shops, and bidding up prices. The next day, they may decide to pay off their debts, leaving the shop owners with unsold inventories they have to get rid of at fire sale prices. So prices may go up when people are in a buying frenzy and may go down when sales dry up.

When there is a buying frenzy business owners are optimistic and do a lot of investments, and often they go into debt to make those investments. But if suddenly customers disappear, they may be stuck with unsold inventory and debts they cannot repay. Businesses may then have to fire people. Those people are then left without income, and cannot repay their debts too, so sales will go down further. If their debts are not repaid, banks could get into trouble. In most cases the economy will recover. In the worst case banks go bankrupt, money disappears, the economy collapses, and an economic depression takes off.

Interest can make things worse. Assume that you have a business and expect to make a return of 8%. You have € 100,000 yourself and you borrow € 200,000 at 6%. You expect to make 8% so borrowing money at 6% seems a good idea. If you only invest your own € 100,000 you can make € 8,000, but if you borrow an additional € 200,000 you can make € 12,000 (8% of € 300,000 minus 6% of € 200,000, which is € 24,000 minus € 12,000). The balance sheet of your business might look like this:

debit		credit
inventory	€ 250,000	loan 6%	€ 200,000
cash, bank deposits	€ 50,000	owner’s equity	€ 100,000
total	€ 300,000	total	€ 300,000

If sales disappoint and you only make a return of 2% on your invested capital of € 300,000, which is € 6,000, you make a loss because you pay € 12,000 in interest charges. You may have to fire workers. Businesses can go bankrupt because they have borrowed too much and have to pay interest, even when they are profitable overall. Sales often disappoint when the economy fares poorly. This means that more businesses face the same difficulties and make losses because of interest payments. They may have to fire workers and these workers lose their income. This can worsen the slump.

Interest, economic depressions and war

Silvio Gesell discovered that interest rates can’t go below a certain minimum because lending would then stop. Money would go on strike as he put it. Why is that? Low yields make investing and lending money unattractive because of the risks involved. Debtors may not repay and banks may go bankrupt. Depositors then prefer to take their money out of the bank and keep it with themselves.

This can cause economic crises and depressions. Silvio Gesell lived around 1900. Interest rates below zero weren’t possible because of the gold standard. Depositors could go to the bank and withdraw their deposits in gold so that they didn’t have to accept negative interest rates. From time to time there were bank runs, economic crises and wars that destroyed a lot of capital. And this created new room for growth.

There may be a relationship between interest, economic depressions and war. In 1910 the amount of capital income (the red circle in the graph) relative to total income (the two circles together) was close to what it was in 2010. This could have led to an economic depression but then came World War I. The war destroyed a lot of capital so that there was new room for capital growth and interest rates could remain positive.

A few decades later the Great Depression arrived. If interest rates could have gone below zero in the 1930s, the Great Depression might not have happened, Adolf Hitler would not have risen to power and World War II would not have occurred. The currency of Wörgl demonstrates that negative interest rates could have ended the depression. After World War II interest rates never came near zero again. Governments and central banks printed more money. This caused inflation, which eroded trust in money.

People feared that inflation would make their money worth less so interest rates rose. In the 1970s the link between money and gold was abandoned because there was a lot more money than there was gold to back it. In the 1980s governments and central banks started policies to bring down inflation and to promote trust in money. As of 1983 interest rates went down gradually as a consequence of a renewed trust in money and central banks. Debt levels rose and interest rates went near zero.

Promoting inflation might not be a good idea. The end result is unpredictable. The best one can hope for is a poor performing economy and a lot of inflation like in the 1970s. But if interest rates rise because lenders lose their trust in money and debts, people may not be able to repay their debts, and the financial system might get into serious trouble. This can cause another great depression or another great war. But if the alternative is negative interest rates, stability and prosperity, then why not opt for that?

Featured image: Of Usury, from Brant’s Stultifera Navis (the Ship of Fools). Albrecht Dürer (1494). Public domain.