Tangible fixed assets are measured at cost less accumulated depreciation and any accumulated impairment losses. 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:

Work in progress is stated at the lower of costs incurred in the purchase of land plus the various costs incurred in obtaining the relevant planning permissions, and the estimated selling price of the land less associated costs. At each reporting date, work in progress is assessed for impairment. If work in progress is impaired the carrying amount is reduced to its selling price less costs to complete and sell, and the impairment loss is recognised immediately in profit or loss.