Japan and Asia are completely different.
Asia is a HUGE place - dwarfing the US, Europe - and most of the world (China alone has more population that Europe + US combined!). All the territories are different, and different consoles launch in different countries at different times.
From a sales point of view, I can see two options:
a) Replace "Japan", with "Asia" - and have a country by country breakdown.
b) Add a 4th territory - "Asia" - which excludes Japan completely. This would include (but not be limited to): HongKong, China, Taiwan, Singapore, Korea, Mayalsia, Indonesia, Vietnam, Philippines.
The major territories are HongKong, Singapore, Taiwan & Korea. China (more?) rarely gets consoles (ironic considering most are made there!). Singapore is "culturally" close to the West, and gets a lot of stuff that Australia gets. Taiwan is a bit of both (and is technically a part of China - politically anyway). And Korea is a huge (PC) gaming market - Nintendo stated they were going to target Korea as a market.
Some countries are PAL - and some are NTSC (not sure which).
I think extrapolating *any* figures for these regions (from Japan) is completely wrong. Some of the markets are huge, and deserve to be counted in their own rights. And shipments are never sent to Japan, then "split" to other Asian regions.
My question to everyone - is Australia / NZ actually part of Europe, or part of Asia.
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Im not sure how sales figures are stored (re: this site) at the back-end, but maybe something like this would work:
- maintain a list of every individual country/territory (no overlap between each)
- mark each country/region with a list of attributes, defining where it is. Some example attributes could include "Asia", "Japan", "Southern Hemisphere", "Europe", "UK", etc..
As far as the main figures go, always possible to have a "Rest of World" - and show a list of countries that are counted.