If the entity engages in foreign currency transactions, the relative value between the different currencies is managed via exchange rates.
valid_from: The date from which the exchange rate is valid.valid_to: The date at which the exchange rate ceases to be valid. Defaults to null.currency: The Currency object for the foreign currency.entity: The Entity associated with the exchange rate. Defaults to the the entity of the logged in user.rate: Rate of exchange between the foreign currency and the reporting currency. Defaults to 1.00$exchangeRate->attributes(): Presents the exchange rate’s attributes as an object. Useful for debugging.$exchangeRate->toString():The string representation of the Exchange Rate object instance.