Introduction

Where people trade with each other, there are prices involved – either explicitly, when for the provision of goods or services has to be paid with money, or implicitly, when there is payment in kind. Over the course of history people have expressed concerns about fluctuations of prices, especially of daily necessities such as bread. Also, though to a lesser extent, regional price differences were a source of concern. Since sharp price fluctuations easily led to social unrest, authorities considered it their task to regulate prices. And price regulation presupposes price measurement. Though the systematic measurement of price changes and price differences had to wait until the emergence of official (national) statistical agencies around the turn of the 20th century, there are numerous examples of individuals and authorities who were engaged in price measurement and/or regulation.

A rather famous example is the Edict on Maximum Prices (Edictum de Pretiis Rerum Venalium), issued by the Roman emperor Diocletianus in the year 301. Along with a coinage reform, the Edict declared maximum prices for more than a thousand commodities, including food, clothing, freight charges, and wages. This turned out to be not very helpful, because the continued money supply increased inflation, and the maximum prices were apparently set too low.

An interesting case is the regulation on bread prices that was issued by the municipal council of Gdańsk in 1433 (see Kula 1986, chapter 8). Here the price of bread was fixed through time, while fluctuations in the supply of corn were to some extent accommodated by letting the weight of a loaf vary. Technically speaking, the unit of measurement was allowed to vary.