Full Professional Members
| 2019 | 2020 | |
| Estonia | – | 7 |
| Germany | 422 | 501 |
| Greece | 44 | 43 |
| Hungary | 78 | 89 |
| Italy | 293 | 364 |
| Latvia | 38 | 39 |
| Netherlands | 100 | 103 |
| Poland | 32 | 39 |
| Russia | 44 | 43 |
| Spain | 61 | 70 |
| UK | 270 | 353 |
| Total number | 1382 | 1651 |
Full Basic Members
| 2019 | 2020 | |
| Austria | 53 | 62 |
| Belgium | – | 19 |
| Czech Rep. | 44 | 10 |
| Finland | 82 | 83 |
| France | 43 | 35 |
| Slovenia | – | 6 |
| Switzerland | 81 | 79 |
| Ukraine | 75 | 112 |
| Total number | 378 | 406 |
Associate Members
| 2019 | 2020 | |
| Croatia | 10 | 10 |
| Cyprus | 10 | 12 |
| Denmark | 22 | 21 |
| Israel | 321 | 348 |
| Portugal | 9 | 10 |
| Romania | 30 | 22 |
| Sweden | 39 | 39 |
| Total number | 441 | 462 |