| Year Joined | Country | % Correct |
|---|---|---|
| 1949 | Belgium | 95%
|
| United States | 89%
| |
| Canada | 85%
| |
| Denmark | 85%
| |
| 2023 | Finland | 85%
|
| 2024 | Sweden | 85%
|
| France | 82%
| |
| Turkey | 82%
| |
| 1952 | Greece | 80%
|
| 1982 | Spain | 80%
|
| United Kingdom | 80%
| |
| 2004 | Bulgaria | 79%
|
| 1999 | Czech Republic | 79%
|
| Estonia | 79%
| |
| 1955 | Germany | 79%
|
| Italy | 79%
| |
| Netherlands | 79%
| |
| 2020 | North Macedonia | 79%
|
| Portugal | 79%
| |
| 2009 | Albania | 77%
|
| Latvia | 77%
| |
| Luxembourg | 77%
| |
| Poland | 77%
| |
| Slovakia | 77%
| |
| Lithuania | 75%
| |
| 2017 | Montenegro | 75%
|
| Slovenia | 75%
| |
| Croatia | 74%
| |
| Hungary | 74%
| |
| Iceland | 74%
| |
| Norway | 72%
| |
| Romania | 72%
|