Nintendo's stock down since 'Super Mario Run' release

Despite solid sales of "Super Mario Run" since the smartphone game's release, Nintendo shares have dropped 11 percent since it launched Thursday.

Reviews of the game by customers have been sub-par, and investors also worry about the $10 price tag to unlock all the levels.

It's prompted some to worry about how long the game can continue to bring in money. Many other mobile games use smaller in-game transactions to expand the revenue stream.

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