Exchange rates
The rate on a document is the rate that governed its date and its purpose — the supplier's invoice, the customs declaration, the books, the bank, the revaluation.
The same day carries different rates for different purposes, and they are kept apart: what the supplier invoiced at is not what customs valued at, and neither is what the bank settled at.
| Date | Currency | Purpose | Rate | Source |
|---|---|---|---|---|
| No rate has been recorded yet. | ||||
The conversion is stored against the document it belongs to, and the database re-derives it from the rate — so a rate changed afterwards is refused rather than leaving a posted figure that no longer follows from it.
What the open items in a foreign currency are worth at the closing rate, read from the subledgers and posted. It used to take the balances in the request, which meant a month end could be closed on figures somebody typed.