Margins
| TTM | 2018 | 2017 | 2016 | 2015 | 2014 | |
|---|---|---|---|---|---|---|
| Gross margin | 53.2% | 53.2% | 52.7% | 52.7% | 52.3% | 52.1% |
| Gross margin growth (bps) | 53 | 53 | -2 | 44 | 21 | 25 |
| Operating margin | 16.1% | 16.1% | 19.1% | 19.4% | 19.2% | 19.3% |
| Operating margin growth (bps) | -306 | -297 | -27 | 20 | -14 | -7 |
| Net profit margin | 11.9% | 11.9% | 11.8% | 11.7% | 11.4% | 11.3% |
| Net profit margin growth (bps) | 16 | 16 | 9 | 28 | 10 | 18 |