- Ratio of orders booked to revenue in the period.
- Before exceptional items, acquisition related costs, acquired intangible asset amortisation and share-based payment amounting to $4.3 million in total (2018 $19.6 million).
- Adjusted operating profit as a percentage of revenue in the period.
- Adjusted basic earnings per share is based on adjusted earnings as set out in note 11 of Notes to the full year consolidated financial statements.
- Operating cash flow after tax, net interest and net capital expenditure and lease payments/sublease income.
Items with notes 1 to 5 above are non-GAAP alternative performance measures, see pages 190 and 191 of the Spirent Communications plc Annual Report 2019 for more detail.