The Commission, by 28 December 2011 and every three years thereafter, shall present to the European Parliament and to the Council a comprehensive report on the application of this Directive. This report shall, in accordance with Article 16(4), address in particular the application of Article 16. It shall also consider the need for additional measures for matters excluded from the scope of application of this Directive. It shall be accompanied, where appropriate, by proposals for amendment of this Directive with a view to completing the Internal Market for services.