Impairment of assets
The carrying values of property, plant and equipment are reviewed for impairment when events or changes in circumstances indicate the carrying value may be impaired. If any such indication exists, the recoverable amount of the asset is estimated in order to determine the extent of impairment loss. Where it is not possible to estimate the recoverable amount of an individual asset, the Group estimates the recoverable amount of the cash-generating unit to which it belongs.
An asset’s recoverable amount is the higher of an asset’s or cash-generating unit’s fair value less costs to sell and its value-in-use. In assessing value-in-use, its estimated future cash flow is discounted to its present value using a pre-tax discount rate that reflects the current market assessment of the time value of money and the risks specific to the asset.