(5)Trading venues should store data that is comprehensive and allows competent authorities and ESMA to perform accurate calculations. While the required information is usually provided in the post-trade reports, in some cases, the information necessary for the calculations goes beyond the information available in those reports. This includes, for example, information on transactions executed on the basis of orders that benefitted from the large in scale waiver. This information should not be included in trade reports since it could expose such transactions to adverse market impact. However, since that information might be necessary for competent authorities to perform accurate calculations, it should be stored appropriately by trading venues, APAs and CTPs and communicated to competent authorities and ESMA where necessary. Trading venues should ensure that they adequately disseminate the information to be provided to competent authorities and ESMA. Transactions executed on the basis of large in scale orders should be appropriately identified in their report to CTPs.