Never really counted the nationalities - but I gues 60 or so might be right... the website should know after all....
Just for your friends mentioning... I do know a couple germans, belgiums, hungarian, austrian, of course british, french, ... and pilots from all parts of africa (south africa, zimbabwe, ....) flying for EK.
60 seems a big number - but somehow it adds up quickly if you throw in some of the "smaller" countries as well- like jamaica, mexico, kroatia, .... and you only need 1 from a country to make it count!