cursory searches for income maps of Tokyo and Japan not sure how recent or accurate they are, but the Tokyo map ranges from about $48K to $70K, while the Japan one ranges from $34K to $61Kpic.twitter.com/lItNJYj9cA
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I'm not sure off the top of my head (and I'm also surprised that Shikoku is better off than Okinawa and most of Kyushu)