(11)It is important to avoid the risk of larger trading venues using calculation methods that minimise their annual notional amount with the aim of benefiting from the opt-out mechanism to the access provisions. Where there are equally accepted alternative approaches to calculating notional amount, using the calculation which gives the higher value helps avoiding that risk. The methods used for calculating notional amount for the purposes of Regulation (EU) No 600/2014 should enable genuinely smaller trading venues that have not yet acquired the technological capability to engage on an equal footing with the majority of the post-trade infrastructure market to make use of the opt-out mechanism. It is also important for the methods prescribed to be straightforward and unambiguous in order to contribute to consistent and uniform supervisory practices.