Tangible fixed assets are measured at cost less accumulated depreciation and any accumulated impairment losses or at a revalued amount.
Any tangible assets carried at a revalued amount are recorded at the fair value at the date of revaluation less any subsequent accumulated depreciation and subsequent accumulated impairment losses.
An increase in the carrying amount of an asset as a result of a revaluation is recognised in other comprehensive income and accumulated in capital and reserves. However, the increase is recognised in profit or loss to the extent that it reverses a revaluation decrease of the same asset previously recognised in profit or loss. A decrease in the carrying amount of an asset as a result of revaluation is recognised in other comprehensive income to the extent of any previously recognised revaluation increase accumulated in capital and reserves. If a revaluation decrease exceeds the accumulated revaluation gains accumulated in capital and reserves in respect of that asset, the excess is recognised in profit or loss.
Depreciation is provided at rates calculated to write off the cost of the fixed assets, less their estimated residual value, over their expected useful lives on the following bases: