| EUR thousand | 2018 | 2017 | |
| Purchases of material, supplies, and goods | 23,896 | 18,567 | |
| Change in inventories | -2,031 | -1,406 | |
| Warranty expenses | -66 | 134 | |
| External services | 829 | 597 | |
| Total | 22,628 | 17,892 | |
| EUR thousand | 2018 | 2017 | |
| Purchases of material, supplies, and goods | 23,896 | 18,567 | |
| Change in inventories | -2,031 | -1,406 | |
| Warranty expenses | -66 | 134 | |
| External services | 829 | 597 | |
| Total | 22,628 | 17,892 | |