Participating Countries by Survey Years
Main content
| Ìý | 1983/84 | 1985/86 | 1989/90 | 1993/94 | 1997/98 | 2001/02 | 2005/06 | 2009/10 | 2013/14 | 2017/18 |
| Albania | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ |
| Armenia | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ |
| Austria | √ | √ | √ | √ | √ | √ | √ | √ | √ | √ |
| Azerbaijan | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ |
| Belgium (Flemish) | Ìý | Ìý | √* | √ | √ | √ | √ | √ | √ | √ |
| Belgium (French) | Ìý | √ | √* | √ | √ | √ | √ | √ | √ | √ |
| Bulgaria | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ | Ìý | √ | √ |
| Canada | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ | √ |
| Croatia | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ |
| Czech Republic | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ |
| Denmark | √** | √** | √** | √ | √ | √ | √ | √ | √ | √ |
| England | √ | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ |
| Estonia | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ |
| Finland | √ | √ | √ | √ | √ | √ | √ | √ | √ | √ |
| France | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ |
| Georgia | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ |
| Germany | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ |
| Greece | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ |
| Greenland | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ |
| Hungary | Ìý | √ | √ | √ | √ | √ | √ | √ | √ | √ |
| Iceland | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ |
| Ireland | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ |
| Israel | Ìý | √ | √ | √ | √ | √ | √ | √ | √ | √** |
| Italy | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ |
| Kazakhstan | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ |
| Latvia | Ìý | Ìý | √** | √ | √ | √ | √ | √ | √ | √ |
| Lithuania | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ |
| Luxembourg | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ |
| Malta | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ |
| Moldova | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ |
| Netherlands | Ìý | √** | √** | Ìý | Ìý | √ | √ | √ | √ | √ |
| North Macedonia | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ |
| Northern Ireland | Ìý | Ìý | √** | √ | √ | Ìý | Ìý | Ìý | Ìý | Ìý |
| Norway | √ | √ | √ | √ | √ | √ | √ | √ | √ | √ |
| Poland | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ | √ |
| Portugal | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ |
| Romania | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ |
| Russian Federation | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ | |
| Scotland | Ìý | √ | √ | √ | √ | √ | √ | √ | √ | √ |
| Serbia | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ |
| Slovakia | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ | √ | √ |
| Slovenia | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ |
| Spain | Ìý | √ | √ | √ | Ìý | √ | √ | √ | √ | √ |
| Sweden | Ìý | √ | √ | √ | √ | √ | √ | √ | √ | √ |
| Switzerland | Ìý | √ | √ | √ | √ | √ | √ | √ | √ | √ |
| Turkey | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | Ìý | √** |
| Ukraine | Ìý | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | √ |
| USA | Ìý | Ìý | Ìý | Ìý | √ | √ | √ | √ | Ìý | Ìý |
| Wales | Ìý | √ | √ | √ | √ | √ | √ | √ | √ | √ |
Ìý* a single national file was submitted
** carried out survey after scheduled fieldwork dates
30.08.2021