(4)Harmonisation of data formats for the transmission of data to CTPs facilitates efficient reception and processing of input data. Harmonisation of data formats for the data transmission also streamlines the operations of CTPs in consolidating and disseminating data in a cost-efficient manner, reducing complexity, enhancing overall operational effectiveness and ensuring the consistency and quality of data for the users of a CTP. The ISO 20022 standard sets out a methodology that provides for harmonisation at three levels: the conceptual level specifying the semantics of data, the logical level specifying the message model without regard to technology, and the physical level describing the syntax of the message in a technology that is used for the transmission of data. Given the broad adoption of ISO 20022 by markets participants in the context of regulatory reporting, the use of that standard should facilitate the consistency and comparability of data. Therefore, any format used by data contributors for reporting under Article 22a of Regulation (EU) No 600/2014 should adhere to the methodology laid down in that ISO standard. However, given the varying market practices and their level of maturity across different asset classes, adherence to a single syntax at a third level is not necessary where well-established market practice already exists, including in the case of the equity asset class. Adherence to the methodology laid down in the ISO 20022 standard is ensured where a mapping is provided between a data format and the ISO 20022 model at the conceptual and logical levels.