If you want to understand the potential effect of the exchange rate on a multicurrency transaction, you need to determine the unrealized gain or loss for the transaction. Unrealized gain or loss affects only open (unpaid) transactions; it reflects the money you'd make or lose either by receiving payment for a sale or by making payment on a debt using the current exchange rate.
Businesses typically calculate this amount for all their open transactions at the end of each accounting period and record a General Journal transaction to account for the potential income or expense. Unrealized gains typically are recorded using an income account, such as "Unrealized Currency Gain/Loss,' along with the exchange accounts for your foreign-currency accounts. You should consult your accountant to determine whether your business needs to track unrealized gains and losses, and if necessary, the most appropriate way to do so.
To determine the unrealized gain or loss for a particular accounting period, print the MYOB AccountEdge Currency - Unrealized Gain/Loss report. This report shows the original and current value of your open transactions in US dollars, along with the total gain or loss as of the date you've selected. (Assigning accounts to foreign currencies)