Current tax — UK corporation tax2.34.5
— overseas tax at prevailing local rates11.57.8
— adjustment in respect of prior years(0.4)(0.9)
Total current tax expense13.411.4
Deferred tax — origination and reversal of temporary differences(9.2)(9.5)
— adjustment in respect of tax rates(11.2)
— adjustment in respect of prior years(0.2)0.6
Total deferred tax credit(20.6)(8.9)
Total income tax (income)/expense in the Consolidated Income Statement(7.2)2.5

The tax on the Group's profit before taxation differs from the standard rate of UK corporation tax of 19.00% (2017: 19.75%). The differences to this rate are explained below:

Profit before taxation28.928.6
Tax at 19.00% (2017: 19.75%)5.55.6
Effect of:
— expenses not deductible0.50.2
— acquisition expenses0.70.6
— research and development related tax credits(0.1)(0.1)
— patent box tax credits(2.6)(2.1)
— impact of financing (income not taxable)(0.5)(0.7)
— effects of overseas tax rates1.0(0.7)
— movement in unrecognised deferred tax0.1
— adjustment in respect of prior years(0.6)(0.3)
— change in tax rates(11.2)
Total income tax (income)/expense in the Consolidated Income Statement(7.2)2.5

Recurring items in the tax reconciliation include: research and development related tax credits and patent box incentives; expenses not deductible; and the impact of financing. The effective tax rate is -24.9% (excluding non-underlying items the effective tax rate is 20.5%).

Tax Credit/(Charge) Recognised Directly in Equity

Deferred tax on employee benefit obligations(0.5)
Tax recognised in Consolidated Statement of Comprehensive Income(0.5)
Corporation tax on equity settled transactions1.00.7
Deferred tax on equity settled transactions0.90.1
Total tax recognised in Equity1.90.8

The UK current tax rate used for the period is 19.00% which is the enacted rate from 1 April 2017. Finance Act 2016 which was substantively enacted in September 2016 included provisions to reduce the rate of corporation tax to 17% with effect from 1 April 2020. Deferred tax has been calculated using the rate of 19% and 17% based on the timing of when each individual deferred tax balance is expected to reverse in the future. Similarly, deferred tax arising in overseas jurisdiction has been based on the enacted rate.

US Tax Reform and EU CFC Challenge

The United States Tax Cuts and Jobs Act was signed on 22 December 2017 and included a broad range of tax reform measures including a reduction in the Federal rate of corporate income tax from 35% to 21% (effective 1 January 2018) as well as significant changes to business deductions and other international tax provisions including changes to the rules governing interest deductibility. In the results to 30 June 2018 US tax reform gave rise to a transitional one-off non-underlying non-cash tax credit of £10.0 million primarily due to the revaluation of the Group's aggregate US deferred tax assets and deferred tax liabilities following the reduction in the US Federal rate from 35% to 21%.

Finance arrangements are in place to fund the acquisition of business operations in overseas territories. This finance is provided primarily to US operations through intragroup loans which provide a benefit to the Group effective tax rate. In addition, the Group claims a partial exemption under the UK Controlled Foreign Companies legislation for profits from 'qualifying loan relationships'. The Group is monitoring the developments in relation to EU state aid investigations into this exemption, noting that at this stage the final outcome of any investigation is not certain. As such, no quantification of the potential tax liability has been calculated, as the basis for this calculation is currently unclear.

Future Tax Charge

The Group's future tax charge, and its effective tax rate could be affected by several factors including the impact of the implementation of the OECD's Base Erosion and Profit Shifting ('BEPS') actions, and changes in applicable tax rates and legislation in the territories in which it operates.