[sarasi]

I think you are perhaps thinking of English-speaking foreigners when you say that most foreigners stay less than a year. The majority of foreigners in Japan are from China and Korea, and they are long-term residents. I don't even mean those who were born in Japan but still hold foreign nationalities- the number of immigrants from those countries vastly outnumber those from western countries.

This is based on statistics I have seen regarding numbers of immigrants from each nationality, but I may be wrong- can you point me towards some statistics which show that most foreigners stay a year or less?

I realise that depending on the area the resident's tax varies by up to a few percentage points. It is not as simple as "people in one area pay $1,200 while people in another pay $7,000" though- a system that charged people from some areas 5 times more than those in others would obviously be unworkable.

The main factor in the amount of tax is the person's income.