| Year | Change | Countries | % Correct |
|---|---|---|---|
| 1957 | +6 | Belgium | France | Germany | Italy | Luxembourg | Netherlands | 100%
|
| 1972 | +3 | Denmark | Ireland | United Kingdom | 96%
|
| 2003 | +10 | Cyprus | Czech Republic | Estonia | Hungary | Latvia | Lithuania | Malta | Poland | Slovakia | Slovenia | 91%
|
| 1985 | +2 | Portugal | Spain | 90%
|
| 1994 | +3 | Austria | Finland | Sweden | 89%
|
| 1979 | +1 | Greece | 87%
|
| 2005 | +2 | Bulgaria | Romania | 85%
|
| 2012 | +1 | Croatia | 85%
|
| 2020 | -1 | United Kingdom | 80%
|