http://www.legislation.gov.uk/eur/2020/1148/article/21/adoptedCommission Implementing Regulation (EU) 2020/1148 of 31 July 2020 laying down the methodological and technical specifications in accordance with Regulation (EU) 2016/792 of the European Parliament and of the Council as regards harmonised indices of consumer prices and the house price index (Text with EEA relevance)Commission Implementing Regulation (EU) 2020/1148Commission Implementing Regulation (EU) 2020/1148 of 31 July 2020 laying down the methodological and technical specifications in accordance with Regulation (EU) 2016/792 of the European Parliament and of the Council as regards harmonised indices of consumer prices and the house price index (Text with EEA relevance)2020-12-12King's Printer of Acts of Parliamenthttps://webarchive.nationalarchives.gov.uk/eu-exit/https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32020R1148texttext/xmlen CHAPTER 2 <Strong>HARMONISED INDEX OF CONSUMER PRICES AND HARMONISED INDEX OF CONSUMER PRICES AT CONSTANT TAX RATES</Strong> Harmonised index of consumer prices at constant tax rates Article 21 1 An individual tax in scope for the HICP-CT shall be taken into account if its annual revenue represents 2 % or more of the sum of all individual taxes in scope collected by general government sector. 2 The annual revenue from taxes taken into account in the HICP-CT shall cover at least 90 % of the sum of all individual taxes in scope collected by general government sector. 3 The HICP-CT shall be compiled in the same way as the HICP, except that observed prices are adjusted so that the tax rates on products are kept constant in the observation period, as compared with the price reference period. 4 Changes in tax rates shall be reflected in the HICP-CT: a in the month for which the new rate is applied to the individual product and included in the observed price; or b in the first entire month for which the new rate is applicable. Rate changes that enter into force on the first day of the month shall be reflected in the HICP-CT for that month. Rate changes that enter into force later that month shall be reflected in the HICP-CT for the following month.