Property, plant and equipment and intangible assets with finite useful lives are tested for impairment if events or changes in circumstances (assessed at each reporting date) indicate that the carrying amount may exceed the recoverable amount.
When an impairment test is performed, the recoverable amount is assessed by reference to the higher of the value in use of the relevant cash generating unit and the fair value less cost to sell. The value in use is determined as the net present value of the future cash flows expected to be derived from the asset, discounted using a pre-tax discount rate that reflects current market assessments of the time value of money and the risks specific to the asset.
Goodwill and intangible assets with indefinite useful lives are reviewed for impairment at least annually.