The calculation of the basic and diluted earnings per share is based on the following data:
| 2017
£m | 2016
£m |
| Earnings | | |
| Earnings for the purpose of basic earnings per share being net profit attributable to equity holders of the parent | 97.1 | 67.0 |
| Number | Number |
| Number of shares | | |
| Weighted average number of ordinary shares for the purpose of basic earnings per share | 190,250,855 | 190,166,794 |
| Effect of dilutive potential ordinary shares: | | |
| Share options | – | – |
| Weighted average number of ordinary shares for the purpose of diluted earnings per share | 190,250,855 | 190,166,794 |
| Pence | Pence |
| Earnings per share: | | |
| Basic | 51.0 | 35.2 |
| Diluted | 51.0 | 35.2 |
| £m | £m |
| Headline earnings | | |
| Net profit attributable to equity holders of the parent | 97.1 | 67.0 |
| Add back: | | |
| Amortisation of acquired intangible fixed assets (net of tax) | 2.9 | 2.8 |
| Acquisition costs (net of tax) | – | 0.5 |
| Less: | | |
| Impact of US Tax Cuts and Jobs Act treated as an exceptional item | (6.4) | – |
| Headline earnings | 93.6 | 70.3 |
| Pence | Pence |
| Headline earnings per share: | | |
| Basic | 49.2 | 37.0 |
| Diluted | 49.2 | 37.0 |