| Joined | Country | % Correct |
|---|---|---|
| 1949 | United Kingdom | 98%
|
| 1949 | France | 97%
|
| 1949 | United States | 97%
|
| 1955 | Germany | 96%
|
| 1982 | Spain | 95%
|
| 2024 | Sweden | 95%
|
| 2023 | Finland | 93%
|
| 1949 | Italy | 93%
|
| 1949 | Norway | 93%
|
| 1949 | Portugal | 93%
|
| 1999 | Poland | 92%
|
| 1949 | Canada | 91%
|
| 1949 | Belgium | 90%
|
| 1949 | Denmark | 89%
|
| 1949 | Netherlands | 89%
|
| 1952 | Greece | 88%
|
| 2004 | Estonia | 85%
|
| 2004 | Latvia | 85%
|
| 2009 | Croatia | 84%
|
| 1999 | Hungary | 84%
|
| 2004 | Lithuania | 84%
|
| 2004 | Slovakia | 84%
|
| 2004 | Slovenia | 83%
|
| 1999 | Czech Republic | 82%
|
| 2004 | Romania | 82%
|
| 1952 | Turkey | 82%
|
| 2004 | Bulgaria | 80%
|
| 1949 | Luxembourg | 79%
|
| 1949 | Iceland | 78%
|
| 2009 | Albania | 77%
|
| 2020 | North Macedonia | 69%
|
| 2017 | Montenegro | 66%
|