(21)To ensure a proper calibration of the thresholds for the application of pre-trade equity transparency requirements to systematic internalisers, the methodology to determine the standard market size (‘SMS’) set out in Article 11 of Delegated Regulation (EU) 2017/587 should be refined by increasing the granularity of the average trade size buckets. The threshold to determine the minimum quote size for systematic internalisers should correspond to the SMS. Taking into account the international best practices, the competitiveness of Union firms, the significance of the market impact, and the efficiency of price formation, the threshold to determine the size up to which pre-trade equity transparency obligations apply to systematic internalisers should correspond to twice the SMS.