I have finally edited the statistics and crime rate of foreigners in Japan, this time based on the number of visitors + residents instead of just residents, as it is obvious that the number of people arrested does not take visa status into consideration, but only nationality.

Thanks you for pointing that out.

It now appears, as I suspected, that Westerners in Japan (residents or visitors) commit in average 15x less crimes than the Japanese. This is only natural, as tourists do not normally commit crimes, and most Western residents came to Japan by themselves, either as well-paid expats, diplomats, spouses of Japanese citizens, university students or, for the biggest part, people who are so interested by Japan and its culture that they decided to fly to the other end of the world (well, at least for Europeans and Americans) to live in the country that fascinates them. Most crimes must consequently be commited by people coming with some bad intend in mind (drug traffickers, mafia...). Let us not forget that US soldiers in Japan have a very high crime rate, maybe proportionally higher than any other foreign civilians, if we believe this article.