If you click on the "normalized" link, you'll get to a page that says this:

just because a particular region isn't on the Top Regions list for the term "haircut" doesn't necessarily mean that people there have decided to stage a mass rebellion against society's conventions. It could be that people in that region [...] search for so many other topics unrelated to haircuts that searches for "haircut" make up a very small portion of the search volume from that region when compared to other regions.

So Japanese being on top of the list doesn't imply that people who speaks Japanese search more about Perl that people who speaks English. I see it as a proportion, where for example, 4 out of 10 Japanese google for Perl while only 3 out of 10 English do.