| Country | 2004 | 2007 | 2010 |
|---|---|---|---|
| Austria | 6.59 | 3.01 | 0.37 |
| Belgium | 16.75 | 11.18 | 30.71 |
| Bulgaria | 73.94 | 30.33 | |
| Czech Republic | 19.84 | 14.27 | 7.5 |
| Germany | 2.2 | 2.1 | 1.56 |
| Denmark | 0.75 | 0.23 | |
| Greece | 10.04 | 7.31 | 5.48 |
| Spain | 7.42 | 5.23 | 4.72 |
| Finland | 15.72 | 12.73 | 16.68 |
| France | 11.24 | 8.28 | 6.08 |
| Hungary | 12.0 | 4.56 | 6.58 |
| Switzerland | 1.21 | 1.08 | |
| Ireland | 0.66 | 0.26 | 0.15 |
| Italy | 3.79 | 5.55 | 2.61 |
| Lithuania | 15.08 | 10.22 | |
| Netherlands | 8.99 | 8.19 | 5.33 |
| Norway | 24.4 | 19.3 | 20.8 |
| Poland | 12.75 | 19.69 | 14.12 |
| Portugal | 20.94 | 19.56 | 10.53 |
| Sweden | 14.6 | 10.41 | 12.23 |
| Slovakia | 19.26 | 20.52 | 19.54 |
| United Kingdom | 14.92 | 10.85 | 8.22 |