Stocks are valued at the lower of cost and estimated selling price less costs to complete and sell.

In the case of finished goods and work in progress, cost is defined as the aggregate cost of raw material, direct labour and attributable proportion of direct production overheads.

Estimated selling price is based on normal selling price, less further costs expected to be incurred to completion and disposal.

At the end of each reporting period Stocks are assessed for impairment. If an item of stock is impaired, the identified inventory is reduced to its selling price less costs to complete and sell and an impairment charge is recognised in the profit and loss account. Where a reversal of the impairment is recognised the impairment charge is reversed, up to the original impairment loss, and is recognised as a credit in the profit and loss account.

Current tax represents the amount expected to be paid or recovered in respect of taxable profits for the financial year and is calculated using the tax rates and laws that have been enacted or substantially enacted at the Balance Sheet date.

Deferred tax is recognised in respect of all timing differences that have originated but not reversed at the balance sheet date where transactions or events have occurred at that date that will result in an obligation to pay more tax in the future, or a right to pay less tax in the future. Timing differences are temporary differences between the company's taxable profits and its results as stated in the financial statements.

Deferred tax is measured on an undiscounted basis at the tax rates that are anticipated to apply in the periods in which the timing differences are expected to reverse, based on tax rates and laws that have been enacted or substantively enacted by the Balance Sheet date.