In most cases, Greenback uses the exchange rate directly from the transaction as it is given by the upstream provider. When available, this rate is applied to transactions during exporting. Cases in which the exchange rate is not provided, Greenback will use an average historical rate based on an accredited 3rd party lookup table from the day the transaction occurred.
This rate can be manually adjusted during export if necessary. The option is available for both single and bulk exports.
Single transaction export
Bulk transactions export