When trading equities, the return of a position is calculated with the following formulas:
Return = Current Investment - Initial Investment or Return = (Current Price - Average Price) * Quantity
However, when dealing with instruments that have a different currency than the account currency, the FX exchange rate comes into play and affects the calculation of your Result:
Return = (Current Price / Current FX rate - Average Price / Average FX rate) * Quantity
It is important to note that the Return figure shows your position's ongoing result, while Gain/Loss and FX Impact are used to visualise the effects currency fluctuations may have on your investment:
Return = Gain/Loss + FX impact