Prof. Dr. Malte Krüger

Payment Systems

The topic of payment systems has many facets. The range of topics in my publications on payment transactions is correspondingly broad.

One topic is the role of cash in payment transactions and its macroeconomic impact. Issues such as money laundering, the shadow economy, inclusion, and data protection also play a role in connection with cash.

Over time, there have been many innovations in payment systems. The resulting spread of checking accounts was particularly significant. Later came the spread of card payments and the introduction of new online payment methods. Above all, the development of so-called "e-money" led to great hopes and fears around the turn of the millennium. Blockchain, stablecoins, and digital central bank money are currently important topics.

The last few decades have seen a significant intensification of payment system regulation. In addition to issues of security and consumer protection, the focus was primarily on interventions in the business model of payment systems (keyword: "interchange fees").

Balance of Payments/Exchange Rates/Foreign Exchange Market

My publications in this area were strongly driven by the events of the 1980s and 1990s.

In the 1980s, the focus was on the high current account deficits of the USA and the surpluses of countries like Germany and Japan. The ups and downs of the US dollar also received considerable attention. In the 1990s, the focus was initially on the rapid turnaround in the German current account balance, followed by the problems in the European Monetary System. In the economic debate, the role of financial markets was repeatedly emphasized, with the role of currency speculators often being critically targeted. I have addressed all of these aspects in my academic work.

Monetary Policy and Theory

A focus of my work in this area is on analyses related to three very closely intertwined discussions from the 1990s. At that time, there was the observation that banks' reserves at the central banks were shrinking. Therefore, the question arose as to what central banks could still do if the demand for cash were to fall to zero. At the same time, there were economists who, given falling transaction costs in the financial markets, expected that transactions would occur without the use of money. Finally, at the end of the 1990s, there was the fear (or hope) that e-money issued by private issuers could displace central bank money. As a result, it was concluded in each case that the influence of traditional monetary policy could be expected to diminish.

Further works relate to individual aspects of monetary theory or policy (including economic history analyses).