6. Member States shall establish an effective system of quality control and traceability of the packaging waste to ensure that the conditions laid down in paragraphs 2 to 5 of this Article are met. That system may consist of electronic registries set up pursuant to Article 35(4) of Directive 2008/98/EC or technical specifications for the quality requirements of sorted waste. It may also consist of average loss rates for sorted waste for various waste types and waste management practices, respectively, provided that reliable data cannot be otherwise obtained. Average loss rates shall be calculated on the basis of the calculation rules established in the delegated act adopted pursuant to Article 11a(10) of Directive 2008/98/EC.