amount_currency

amount_currency records which currency the four amount columns are in. It is USD on every record in the catalogue today.

The column exists rather than being assumed because a currency assumed is a currency that becomes wrong silently the first time it is not USD. A figure rendered without knowing its unit is not a figure.

Shown as: the currency symbol on every amount. When absent: does not occur; a record with amounts and no currency would not render them.