1.The levels of stocks held shall be calculated using the methods set out in Annex III. When calculating stock levels for each category held pursuant to Article 9, those methods shall apply only to the products in the category in question.
2.The levels of stocks held at a given time shall be calculated using data from the reference year determined in accordance with the rules set out in Article 3.
3.Any oil stocks may be included simultaneously in both the calculation of a Member State’s emergency stocks and the calculation of its specific stocks provided that those oil stocks satisfy all the conditions laid down in this Directive for both types of stocks.
4.The methods and procedures for calculating stock levels, as referred to in paragraphs 1 and 2, may be amended in accordance with the regulatory procedure referred to in Article 23(2). In particular, it may prove necessary and beneficial to amend those methods and procedures, including the application of the reduction provided for in Annex III, in order to ensure coherence with IEA practice.