By adding denominations to their coin and banknote series central banks can increase the efficiency of cash payments. In practice, however, they opt for a denominational structure with a relatively low density. The literature holds that this is because of the production costs involved. To test...

In an often-cited article, Caianiello et al. (1982) formulate a “principle of invariance” for currency systems. They build on this principle to explain the distribution of the coins and banknotes in circulation over the different denominations, and to analyze how a currency system adjusts to...

One of the most important results of theoretical research on currency systems is that spacing denominations apart by a factor of two is better than a factor of three as this lowers the average number of notes and coins exchanged in transactions. These theoretical studies also claim that an...

In recent years, numerous central banks throughout the world have introduced plastic banknotes in order to combat counterfeiting and reduce their operating costs. In this paper, we provide an analytical framework that allows central banks to assess whether changing the manufacturing material of...