I did find that fairly absurd about Ireland. In the UK I'm not sure there are enough people taking Welsh or Gaelic in their A-levels to make much of a difference in the data...

If you look at the data for learning languages in school, you'll see Belgium doesn't have any data at all. Possibly because Eurostat only has separate data for Flanders and Francophone Belgium, but not for the two together, or because they find it pointless to add them up. But when it comes to how many people know a foreign language, there Belgium does have data, and I'm really not sure if they consider the other national language(s) as a "foreign" language there or not. In any case, Walloons are notoriously bad at foreign languages whether it's Dutch or English or something else, as bad or even worse than the French themselves. Though there is a distinct improvement these past years - the last fifteen years or so their politicians have actually realized they need a working knowledge of their country's majority language if they don't want to look ridiculous, and that's quite new. While many of the richer Francophone families in Brussels are now sending their children to Dutch-language schools, creating an extreme overpopulation there, firstly because those schools are quite simply a ton better and secondly so their children will end up more or less bilingual.