2. Basis of preparation

The Group financial statements are:

• prepared in accordance with the Companies (Jersey) Law 1991 and both UK-adopted International Accounting Standards (UK-IFRS) and International Financial Reporting Standards (IFRS or IFRSs) as adopted for use in the European Union (the EU) and IFRS Interpretations Committee interpretations (together EU-IFRS). The financial statements also comply with IFRS as issued by the International Accounting Standards Board (IASB). UK-IFRS, EU-IFRS and IFRS as issued by the IASB all differ in certain respects from each other, however, the differences have no material impact for the periods presented;
• prepared on the going concern basis and under the historical cost convention, as modified for the revaluation of certain financial assets and financial liabilities;
• presented in US dollars, the most representative currency of the Group’s operations, and generally rounded to the nearest million;
• prepared using the principal exchange rates set out in note 10; and
• designed to voluntarily include disclosures in line with those parts of the UK Companies Act 2006 applicable to companies reporting under that law.

There has been no change in the basis of preparation of the Group financial statements since the Annual Report for the year ended 31 March 2021.

The use of critical accounting estimates and management judgment is required in applying the accounting policies. Areas involving a higher degree of judgment or complexity, or where assumptions and estimates are significant to the Group financial statements, are highlighted in note 5.