Re:10% (Score 2, Insightful)

This is just opinion based on perception, but I would guess that the black market may be equal in volume of sales, but lower in capital gains due to the prices being so much less. Also, I would predict that both of those levels fluctuate with the rise and fall of economies throughout the world. I.E. the black market in China may be dwindling with the rise of capitalism there. Whereas, it seems the black market in Russia is thriving due to the lack of governmental oversight and increase in corruption. Of course these are just opinion, think what you may.