If there's one thing we've seen this generation, it's that major games have increased in sales, and minor games have decreased. Pokemon was, up until this generation, the most major of them all.
The actual Pokemon growth is far larger than this comparison shows.
This gen, we're looking at
Diamond/Pearl - 18 million
HeartGold/SoulSilver - 10 million + (?)
Platinum - 7 - 9 million
Spinoffs - 16 million
Last gen:
Ruby - 15 million
FireRed/Leaf Green - 10 million
Emerald - 6 million
Spinoffs - 1 million
By the end of the generation, there should have been sold at least 25 million more Pokemon games this gen, than last gen. That's near a double in sales.







