| Intangible assets 2018 | ||||
| EUR thousand | Development expenses | Intangible rights | Other intangible assets | Total |
| Acquisition cost, Jan 1, 2018 | 8,968 | 984 | 263 | 10,215 |
| Additions | 2,200 | 152 | 48 | 2,400 |
| Acquisition cost, Dec 31, 2018 | 11,168 | 1,136 | 311 | 12,615 |
| Accumulated depreciation and impairment, Jan 1, 2018 | 4,674 | 478 | 112 | 5,263 |
| Amortisation | 685 | 119 | 58 | 862 |
| Accumulated depreciation and impairment, Dec 31, 2018 | 5,359 | 597 | 170 | 6,126 |
| Carrying amount, Jan 1, 2018 | 4,295 | 506 | 151 | 4,952 |
| Carrying amount, Dec 31, 2018 | 5,810 | 539 | 141 | 6,489 |
| Intangible assets 2017 | ||||
| EUR thousand | Development expenses | Intangible rights | Other intangible assets | Total |
| Acquisition cost, Jan 1, 2017 | 7,940 | 858 | 146 | 8,944 |
| Additions | 1,028 | 126 | 117 | 1,271 |
| Acquisition cost, Dec 31, 2017 | 8,968 | 984 | 263 | 10,215 |
| Accumulated depreciation and impairment, Jan 1, 2017 | 4,043 | 380 | 63 | 4,485 |
| Amortisation | 578 | 98 | 49 | 725 |
| Impairment | 53 | 0 | 0 | 53 |
| Accumulated depreciation and impairment, Dec 31, 2017 | 4,674 | 478 | 112 | 5,264 |
| Carrying amount, Jan 1, 2017 | 3,897 | 478 | 83 | 4,459 |
| Carrying amount, Dec 31, 2017 | 4,295 | 506 | 151 | 4,952 |
The Group’s intangible rights consist of patents and IT software licenses, and the other intangible assets consist of IT software.
The Group has invested in developing new products and improving the features and manufacturing methods of its existing products. At the end of 2018, the carrying amount of expenses for development in progress totaled EUR 1,048 thousand. In 2018, an addition of EUR 2,200 thousand (2017: EUR 1,028 thousand) was recognized on the balance sheet under research and development expenses.
Impairment testing
An impairment test for the research and development projects in progress was prepared to reflect the statuses on December 31, 2018 and December 31, 2017. The impairment test compares the carrying amount of research and development projects in progress with the recoverable amount of money, which is defined as the present value of future cash flows. The impairment testing did not indicate a need for impairment losses to be recognized.