Sarcasm/irony

Something that is common to Scotland and Denmark is a love for sarcasm/irony (I always get these terms mixed up, possibly because so many other people are mixing them up – what I mean is saying the opposite of what is meant, without any explicit clues that this is the case). I know that Austrians do it, too, but I’ve also noticed that people from East Germany, the USA and Japan (and France according to Phyllis) don’t have a clue. I tried to find something about this on Google, but to no avail. Surely somebody must have made a world map of sarcasm?