When it comes to investing, confidence is a big factor. Today, a few of the Dow Jones Industrial Average's (DJINDICES:^DJI) big losers are suffering from a lack of confidence, and although there are only five blue-chip companies in the red today, the index itself is down 31 points, or 0.22%, as of 12:55 p.m. EDT. IBM (NYSE:IBM) is the biggest loser by far, with shares down 7.7% to knock more than 100 points off the Dow, as IBM is the heaviest-weighted component. We'll look into why IBM is plummeting in a moment, but first let's take a look at some of the other losers.

Top Dow losers
Shares of Hewlett-Packard (NYSE:HPQ) are down 2.4% this afternoon. The fall is likely related to the announcement that the Blackstone Group is walking away from a deal to take Dell (UNKNOWN:UNKNOWN) private. This is bad news not only for Dell shareholders, but also for Hewlett-Packard's, because it shows that Blackstone's management doesn't have much hope that Dell can be turned around -- and HP happens to be in the same situation as the flagging computer-maker. 

McDonald's (NYSE:MCD) is also down more than 2% after the company reported quarterly earnings. McDonald's beat on the top line but missed on the bottom. Revenue was expected to be $6.59 billion but came in higher at $6.61 billion. Analysts had expected earnings of $1.27 per share, but McDonald's posted $1.26 per share. But this slight miss is only part of the reason shares are dropping today. The bigger reason for the decline is probably management's pessimistic sales forecast for April. 

Now back to IBM, the real reason the Dow is lower today. The stock is tanking after the company reported quarterly results that missed on both the top and bottom lines. The company reported EPS of $2.70, while analysts were expecting $3.05 per share. Total profit was $3.03 billion, which fell short of the $3.07 billion IBM reported for the same time frame last year. Revenue declined 5.1% to $23.41 billion, whereas analysts had called for $24.62 billion. 

While I personally don't feel the results were terrible, this report makes investors question how strong IBM really is, and its image of a safe and stable company may be tarnished.

Additionally, General Electric is down 3.8%, while Cisco has lost 1.2%.

Fool contributor Matt Thalman has no position in any stocks mentioned. The Motley Fool recommends McDonald's. The Motley Fool owns shares of International Business Machines. and McDonald's. Check back Monday through Friday as Matt explains what caused the Dow's winners and losers of the day, and every Saturday for a weekly recap. Follow Matt on Twitter: @mthalman5513. 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.