With considering iPhone Barista Saraly Index, price of iPhone represents economic disparity well. At Los Angels, saraly of Starbucks barista is 16.11 USD/hour, then 62 hours work purchases 999USD iPhone Pro 15. In Tokyo, saraly is 1,140 JPY/hour, then civil need to work 140 hours to buy 159,800 JPY iPhone Pro 15. iPhone-BSI shows that purchasing power of Tokyo worker is 50% weaker than LA’s. And it fits my feeling.