(9)In order to ensure consistency with the scope of risks captured in the risk-measurement model, the actual and hypothetical changes in the value of the portfolio should generally only reflect the changes related to market risk factors. However, as it could be challenging to isolate changes related to foreign exchange and commodity risk for non-trading book positions subject to commodity risk and non-trading book positions that do not change linearly with movements in the exchange rate, institutions should be allowed to reflect in the actual and hypothetical changes in the value of the portfolio the changes related to all components determining the value of those non-trading book positions.