Below the first area is Production and the second Sales. Only Suzuki stated 'Other' sales and a total sales figure worldwide. This was over 200,000 short of the production total which is quite a lot. I then estimated the remaining three's 'Other' sales, assuming production and sales didn't vary the same way as Suzuki's. The figures cover the fiscal year April '12 to March '13:
Suzuki: 36% of Suzuki production was in Japan, and 25% of sales. Therefore it made less of its cars in Japan than the other three, but had a bigger percentage of sales in its homeland than the others.
Mazda: 73% of production was at home and 18% of sales. This showed an excessive reliance on domestic production but not very dependent on Japan for car sales.
Mitsubishi: 43% of production was Japanese and 12% of its sales for Japan. Overall it depended less on Japan than the others, it's very poor domestic sales giving it that distinction.
Subaru: 76% of production was in Japan and 22% of sales. This is the most Japanese of the quartet here.
Summary: So how do I rate them?
Suzuki is part owned by VW, but this seems irrelevant as sharing between them is non-existent as far as I know. India and Japan are a plus, but dependence on mainly smaller, less profitable vehicles a minus. Unless the VW deal is more productive - or it can successfully move up market in size - then Suzuki is in a neutral position.
Mazda: Now without Ford and not a very big player is a negative, as is being a small brand at home. Still, with the Yen now undervalued again, new frugal engines and a fullish range of vehicles, quite well placed.
Mitsubishi: Too small to go it alone and no other brands wanting to own it, it seems to me Japanese banks keep it going. Not popular in Japan, it struggles just about everywhere else too. It makes some vehicles for PSA but needs much more of that, and concentrate on the Asia/ Pacific region. Not looking that good.
Subaru: It is far too small to be on its own so now Toyota is investing in it. That takes it from a huge negative to a very positive place. The future looks secure under Toyota's wing.