Institutions shall determine whether a transaction is a long or short position in the primary risk driver or in the most material risk driver in a given risk category by applying either of the following methods:
(a) they shall calculate the delta risk sensitivities of those risk drivers in accordance with Article 325r of Regulation (EU) No 575/2013 and identify the transaction as a long position in a risk driver where the corresponding delta risk sensitivity is positive or as a short position where the corresponding delta risk sensitivity is negative;
(b) they shall assess the dependence of the structure of cash flows of the transactions on that risk driver or the hedging purpose of the transaction with respect to that risk driver and identify the transaction as either long or short position on the basis of that assessment.