The denominations of US coins: a case of institutional evolution

The system of denominations of US coins, which the paper treats as a quasi-genetic trait of the US monetary system, has not been constant since inception but rather has evolved over time in the sense of being subject to innovation and selection. However, all the innovations have disappeared, as have a number of the original denominations. Abstract theories of optimal systems of denominations provide a good explanation of one selection factor, but other important influences include limiting the number of separate denominations and accommodating the requirements of decimal counting. However, even some innovations that ultimately disappeared survived for decades.