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What: Shares of (NASDAQ:AMZN) were taking a dive today, falling 11% after posting weak fourth-quarter results.

So what: The market darling, which had soared during the last year, missed on all three counts: revenue, earnings, and guidance. Amazon said sales increased 20%, to $25.6 billion, but that was short of estimates at $26.06 billion as negative currency translation was partially to blame for the shortfall. Meanwhile, profits grew from $0.21 per share a year ago to $0.51, but that was also below estimates of $0.66. For the current quarter, the company expects top-line growth of 13% to 24%, and operating income near breakeven, both well off the Street's mark.

Now what: Amazon is known for conservative guidance and for providing ranges so wide as to be meaningless, so the above projections could prove to be a low bar for the online giant to hop over. Still, the major question for Amazon investors has to be how long the company can keep its lofty growth rate. CEO Jeff Bezos is well-known for bucking short-term expectations in favor of long-term sacrifices, but at a certain point, the company will have to show meaningful profits. Gross margin continues to improve, meaning Amazon is headed in the right direction, but breakeven net income for the current quarter would be a huge disappointment as Wall Street is expecting a $0.54 per-share profit.

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