Finance costs (net) comprise the following items:
| in € thousand | 2015 | 2016 | 2017 | |||
| Finance income | 5 | 1 | 130 | |||
| Interest on preferred shares | (1,056) | (1,836) | (2,229) | |||
| Cost of issuing preferred shares | (84) | (193) | (345) | |||
| Unrealized FX-losses | 0 | (3) | (2,358) | |||
| Other finance costs | 0 | (17) | 10 | |||
| Finance costs | (1,140) | (2,049) | (4,923) | |||
| Finance costs (net) | (1,135) | (2,048) | (4,793) |