Back in the 1930s, according to John Maynard Keynes, one of the jobs of a district commissioner in Uganda was to inspect and evaluate goats.

The local unit of currency was the goat, so most goods were priced in goats. So when a local sought to discharge a debt by presenting an animal that was exceptionally sick, old or otherwise undesirable, the district commissioner would rule on whether that particular animal was fit to count as a “goat” for transactional purposes — whether it was, as it were, a negotiable goat.

One way of understanding this system is that the relevant economy was in effect on a “goat standard” — the value of its standard currency unit was linked to the value of an underlying commodity. If the value of that commodity decreased relative to other commodities, the value of the currency unit would decrease proportionately (that is, there would be inflation) and vice versa.