Well, it could happen to anyone, couldn’t it? An employee at Deutsche Bank mistyped something, and, as a result, the German bank sent US$6 billion to a client in the United States who wasn’t entitled to it.

Luckily for the employee, the recipient didn’t spend the $6 billion immediately, and the bank was able to get the money back the next day, so the employee didn’t have the loss deducted from their salary.

This was not a big news item; I don’t know why the Guardian even bothered to report it, especially since it happened in June. After all, who of us has not had $30 million or $500 million appear and disappear just as mysteriously from our bank accounts? Who has not accidentally sent a few million extra to the local newsagent and received it back the next day?

But it got me wondering enough to get out the calculator. If Deutsche Bank had not been able to get back that wayward transfer, how long would it have taken for the employee who made the mistake to repay the boss for their typing error?

I don’t know the average wage in Germany, but it’s easy to find the per capita national income (nearly the same as in Australia). It is more than the per capita wage (because it includes all the bosses’ profits) but let’s assume that the erring bank employee (let’s call them “Sam”) received that.

On these assumptions, Sam would have had to work for free for Deutsche Bank for about 150,000 years. (That calculation doesn’t include any allowance for possible wage rises over the next 1,500 centuries, but neither does it include any interest, the rate of which is usually higher than annual wage rises.)

Or, if Sam had a very wide circle of relatives and friends, and 150,000 of them agreed to help discharge Sam’s debt, then, if they all worked for free for a year, Sam and Deutsche Bank would be quits, although Sam might be missing a large part of those 150,000 friends and relatives, who had starved to death during a year of working without pay.

What does this tell us? It tells us that international banks routinely transfer gigantic sums of money around the world, transfers of such size that a single transfer of an amount equal to the total annual income of 150,000 workers is too small to require a routine confirmation by the computer: “Do you really want to send that much?”

And of course the computer would never ask: “What can you have done that entitles you to have that much money?”