(NEW YORK) -- Stocks closed slightly lower Monday. The Dow Jones Industrial Average fell 44 points to 15,837. The S&P 500 lost 8 points, while the Nasdaq dropped 44 points. Investors were encouraged by signs of stability in Argentina and Turkey, two of the emerging markets that got slammed last week.
There's also been concern that China's economic engine is slowing down, potentially dragging other developing countries along with it. Apple reported its earnings Monday, with revenue beating expectations. The company sold more iPads and Mac computers than analysts had expected.
However, the company's iPhone did not meet sales expectations. Apple reported it sold 51 million iPhones last quarter -- analysts expected 56 to 57 million.
Investors in the immediate aftermath of Monday's results seemed to be upset that the number of iPhones sold was significantly below what Wall Street was expecting. Apple's stock dropped more than $30 a share in after-hours trading.
Guidance for Apple's next quarter also is coming in below what investors were expecting.
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