Revenue comprises sales of goods or services provided to customers net of value added tax and other sales taxes, less an appropriate deduction for actual and expected returns and discounts. Revenue is recognised when performance obligations are satisfied and the control of goods or services is transferred to the buyer. Where the performance obligation is satisfied over time, revenue is recognised in accordance with its progress towards complete satisfaction of that performance obligation.

When cash inflows are deferred and represent a financing arrangement, the promised consideration is adjusted for the effects of the time value of money, which is recognised as interest income.

Revenue from the sale of goods is recognised when the significant risks and rewards of ownership of the goods have passed to the buyer (usually on dispatch of the goods), the amount of revenue can be measured reliably, it is probable that the economic benefits associated with the transaction will flow to the entity and the costs incurred or to be incurred in respect of the transaction can be measured reliably.

Revenue from contracts for the provision of professional services is recognised by reference to the stage of completion when the stage of completion, costs incurred and costs to complete can be estimated reliably. The stage of completion is calculated by comparing costs incurred, mainly in relation to contractual hourly staff rates and materials, as a proportion of total costs.  Where the outcome cannot be estimated reliably, revenue is recognised only to the extent of the expenses recognised that are recoverable.

At each reporting period end date, the company reviews the carrying amounts of its tangible assets to determine whether there is any indication that those assets have suffered an impairment loss. If any such indication exists, the recoverable amount of the asset is estimated in order to determine the extent of the impairment loss (if any). Where it is not possible to estimate the recoverable amount of an individual asset, the company estimates the recoverable amount of the cash-generating unit to which the asset belongs.

Recoverable amount is the higher of fair value less costs to sell and value in use. In assessing value in use, the estimated future cash flows are discounted to their present value using a pre-tax discount rate that reflects current market assessments of the time value of money and the risks specific to the asset for which the estimates of future cash flows have not been adjusted.

If the recoverable amount of an asset (or cash-generating unit) is estimated to be less than its carrying amount, the carrying amount of the asset (or cash-generating unit) is reduced to its recoverable amount. An impairment loss is recognised immediately in profit or loss, unless the relevant asset is carried at a revalued amount, in which case the impairment loss is treated as a revaluation decrease.

Recognised impairment losses are reversed if, and only if, the reasons for the impairment loss have ceased to apply. Where an impairment loss subsequently reverses, the carrying amount of the asset (or cash-generating unit) is increased to the revised estimate of its recoverable amount, but so that the increased carrying amount does not exceed the carrying amount that would have been determined had no impairment loss been recognised for the asset (or cash-generating unit) in prior years. A reversal of an impairment loss is recognised immediately in profit or loss, unless the relevant asset is carried at a revalued amount, in which case the reversal of the impairment loss is treated as a revaluation increase.

The tax expense represents the sum of the tax currently payable and deferred tax.

The tax currently payable is based on taxable profit for the year. Taxable profit differs from net profit as reported in the profit and loss account because it excludes items of income or expense that are taxable or deductible in other years and it further excludes items that are never taxable or deductible. The company’s liability for current tax is calculated using tax rates that have been enacted or substantively enacted by the reporting end date.

Deferred tax liabilities are generally recognised for all timing differences and deferred tax assets are recognised to the extent that it is probable that they will be recovered against the reversal of deferred tax liabilities or other future taxable profits. Such assets and liabilities are not recognised if the timing difference arises from goodwill or from the initial recognition of other assets and liabilities in a transaction that affects neither the tax profit nor the accounting profit.

The carrying amount of deferred tax assets is reviewed at each reporting end date and reduced to the extent that it is no longer probable that sufficient taxable profits will be available to allow all or part of the asset to be recovered. Deferred tax is calculated at the tax rates that are expected to apply in the period when the liability is settled or the asset is realised. Deferred tax is charged or credited in the profit and loss account, except when it relates to items charged or credited directly to equity, in which case the deferred tax is also dealt with in equity. Deferred tax assets and liabilities are offset when the company has a legally enforceable right to offset current tax assets and liabilities and the deferred tax assets and liabilities relate to taxes levied by the same tax authority.