The Group makes estimates and assumptions concerning the future. The resulting accounting estimates will, by definition, seldom equal the related actual results. The estimates and assumptions that have a significant risk of causing a material adjustment to the carrying amounts of assets and liabilities within the next financial year are discussed below.

The Group tests annually whether goodwill has suffered any impairment, in accordance with the accounting policy. The recoverable amounts of cash-generating units have been determined based on value-in-use calculations. These calculations require the use of estimates. Refer to note 5 for details on these estimates.

In determining the number of forfeitable shares that will vest due to performance conditions being met, management assesses the attrition rates of staff based on the grades of staff that have been granted awards as well as the historic staff turnover.

As with any enterprise, the Group faces uncertainties in the markets in which it operates and over which it has little or no control. The Group is subject to income tax in numerous jurisdictions and judgement is required in determining the provision for tax.

There are transactions and calculations for which the ultimate tax determination is uncertain during the ordinary course of business. Amounts accrued are based on management’s interpretation of country-specific tax law and the likelihood of settlement. Where the final tax outcome of these matters is different from the amounts that were initially recorded, such differences will impact the current income tax and deferred tax provisions in the period in which such determination is made.

Deferred tax assets are recognised to the extent that it is probable that taxable income will be available in the future against which these can be utilised. Future taxable profits are estimated based on business plans which include estimates and assumptions regarding economic growth, interest rates, inflation and competitive forces.

Changes in the estimates of the consideration could result in the recognition of material adjustments in future periods.

The fair values of all of the identifiable intangible assets acquired as part of a business combination are determined using recognised valuation techniques. Such techniques often rely on forecasts of future cash flows and the use of appropriate discount rates that reflect the risk factors associated with the cash flows.

These valuations are based on information at the time of the acquisition and the expectations and assumptions that have been deemed reasonable by the Group’s management. The risk exists that the underlying assumptions or events associated with such assets will not occur as projected. For these reasons, among others, the actual cash flows may vary from forecasts of future cash flows.

Details of whether BLT acts as a principal or an agent in certain of its transactions is set out in the Revenue Recognition note. This assessment requires an analysis of whether BLT carries inventory risk and the customer's credit risk, whether BLT has the latitude to establish pricing and whether BLT has the primary responsibility for providing the goods or services to the customer.