Current and deferred taxationThe tax expense for the year comprises current and deferred tax. Taxable profit differs from net profit as reported in the profit and loss account because it excludes items of income and expense that are taxable or deductible in other years and it further excludes items that are never taxable or deductible. The current income tax charge is calculated on the basis of tax rates and laws that have been enacted or substantively enacted by the reporting date in the countries where the company and the group operate and generate income.Deferred tax liabilities balances are generally recognised for all timing differences and deferred tax assets are recognized to the extent that:it is probable that they will be recovered against the reversal of deferred tax liabilities or other future taxable profits; andAny deferred tax balances are reversed if and when all conditions for retaining associated tax allowances have been met.Deferred tax balances are not recognised in respect of permanent differences except in respect of business combinations, when deferred tax is recognised on the differences between the fair values of assets acquired and the future tax deductions available for them and the differences between the fair values of liabilities acquired and the amount that will be assessed for tax. Deferred tax is determined using tax rates and laws that have been enacted or substantively enacted by the reporting date.PensionsDefined contribution pension planThe company operates a defined contribution plan for its employees. A defined contribution plan is a pension plan under which the company pays fixed contributions into a separate entity. Once the contributions have been paid the company has no further payment obligations.The contributions are recognised as an expense in the profit and loss account when they fall due. Amounts not paid are shown in accruals as a liability in the balance sheet. The assets of the plan are held separately from the group in independently administered funds.