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Short-term investors who cheered the Federal Reserve's recent decision to delay winding down its bond-buying program received another dose of reality today: It's likely coming sooner rather than later. St. Louis Fed President James Bullard pointed that out today, mentioning that it could happen as soon as October. While the Dow Jones Industrial Average (DJINDICES:^DJI) has bounced back to record highs in September, it's taking a breather, down 0.66% as of 2:45 P.M. EDT. Here are two of the stocks pulling the Dow lower.

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Caterpillar is the largest heavy-equipment manufacturer in the world. Photo Credit: Wikimedia Commons.

Caterpillar's (NYSE:CAT) struggles have been well-documented as the global recovery continues to trudge along almost reluctantly. The company is one of the biggest losers in the Dow today, trading down 2.7% after reporting that global sales from its dealers fell in the last three months. Orders dropped significantly as well, down 10% in August, 9% in July, and 8% in June.

According to Barron's, Joel Tiss of BMO Capital Markets said the weakness was expected, but he also offered a bright side: "On a positive note, comps will begin getting easier over the next few months as the first dip below the double-digit growth range in 2012 didn't occur until September, suggesting this report could be one of the last months of declines at or above the high-single-digit range."

Microsoft (NASDAQ:MSFT) is another big loser today, down 2.2% after CEO Steve Ballmer had his last meeting with industry analysts yesterday. The CEO reiterated that Microsoft has a long road ahead to gaining ground on competitors with its Windows Phone operating system; it remains a distant third place behind phones running Google's Android operating system and Apple's iOS.

The tech giant's stock price wasn't helped by the hype and strong demand for Apple's (NASDAQ:AAPL) new iPhone 5c and iPhone 5s, released for sale today. Apple hasn't announced preorder numbers, but it has some lofty numbers to live up to. According to my colleague Daniel Sparks, "iPhone pre-orders during the first twenty-four hours have increased dramatically over the last three years: 600,000, 1 million, and 2 million in 2010, 2011, and 2012, respectively." Only time will tell if Apple's iPhone 5c and 5s live up to expectations, but one thing is for sure: Apple is still producing a valuable and popular product.

Fool contributor Daniel Miller owns shares of Apple. The Motley Fool recommends Apple. The Motley Fool owns shares of Apple and Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.