The preparation of financial statements requires management and the Board of Directors to make estimates and judgments that affect reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. These estimates are based on historical experience and various other assumptions that management and the Board believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions, significantly impacting TeliaSonera's earnings and financial position.
Management believes that the following areas, all of which are discussed and separately marked in the respective sections of Note 4 “Significant Accounting Policies,” comprise the most difficult, subjective or complex judgments it has to make in the preparation of the financial statements: revenue recognition; income taxes; valuation of intangible and other non-current assets; collecting trade receivables; making provisions for pensions as well as provisions for restructuring activities, minority put options, contingent liabilities and litigation.