Half year to 30 June
Headline operating profit70.161.7
Add back non-cash items:
Depreciation and amortisation29.929.4
Impairment of fixed assets0.40.4
Share-based payments2.12.7
Profit on disposal of property, plant and equipment(0.1)
Headline EBITDA1102.594.1
Net capital expenditure(31.0)(29.7)
Net working capital movement(17.8)(4.5)
Headline operating cash flow53.759.9
Cash cost of restructuring(2.1)(2.3)
Operating cash flow51.657.6
Free cash flow239.442.1
  1. Earnings before interest, tax, depreciation, amortisation, impairment, profit or loss on disposal of property, plant and equipment and share-based payments.
  2. Free cash flow is defined in note 2 to the accounts.

Free cash flow for the period was £39.4m compared to £42.1m in the first six months of 2017. The decrease is mainly a result of a larger net working capital outflow which amounted to £17.8m. This reflects two key items. Firstly, there is an £11m seasonal outflow on trade receivables reflecting the fact that higher revenues in June result in higher outstanding receivables than in December. Secondly, bonuses are paid during the first half of the year, and the working capital outflow associated with these payments was £7m. In 2017, this was actually an inflow as the 2016 bonuses paid in the first half of 2017 were lower than those accrued for the first half of 2017.

The utilisation of restructuring provisions resulted in a cash outflow of £2.1m (H1 2017: £2.3m).

Income taxes paid during the first six months at £11.3m were £3.0m less than the same period last year due to lower tax payments in the US in the first half of the year.

The Group's headline operating cash flow decreased to £53.7m (H1 2017: £59.9m), as higher EBITDA was offset by the difference in working capital movements, explained above. In June, £70.5m was paid out to shareholders for the 2017 special and final ordinary dividends (H1 2017: £20.5m) leaving the Group with closing net cash of £5.6m (30 June 2017: £17.7m).