The widespread use of non-decimal currencies before the decimalization process that lasted well into the twentieth century hinders digital analysis of economic activity. Non-decimal currencies fit poorly into the decimalized world of ready-made digital tools for analysis and visualization of economic data. The premodern world was awash in different systems of non-decimal currencies. The most well known—eventually adopted by the English and many other European regions—was a tripartite structure of twelve pence to the shilling and twenty shillings to the pound. However, even just within Europe, alternative tripartite and even tetrapartite systems were widespread. In other words, the actual value represented by say £3 13s. 4d. cannot be determined without knowing the bases of the shillings and pence units. One strategy to working with such data is to decimalize all values, but this can be cumbersome, error prone, and removes the values from their original context. This paper will introduce an R package called debkeepr that facilitates the reproducible analysis and visualization of tripartite and tetrapartite non-decimal currencies. This paper will demonstrate the basic structure of the debkeepr package and its usefulness in a variety of contexts. The package can help facilitate one-off arithmetic calculations of non-decimal values and makes possible the analysis and visualization of large sets of accounts. The debkeepr package includes data from a practice double-entry account book from Richard Dafforne’s The Merchant’s Mirrour, Or Directions for the Perfect Ordering and Keeping of His Accounts (London, 1660), but this paper will also use the account books of the of the wealthy merchant Jan della Faille de Oude (1515–1582) to show the analytical power of incorporating non-decimal currencies into digital methodologies. Finally, the paper will use the debkeepr package to argue for the significance of relatively small-scale digital projects and tools that can be created and maintained by individuals, are open source, that facilitate reproducibility, and that, therefore, can be maintained over long periods of time.

R, digital history, economics, reproducibility