The Dow Jones Industrial Average (^DJI 0.56%) started this week on a three-day winning streak and managed to stretch the rally Monday and Tuesday. And although the index closed down on Wednesday, it lost only five points after gaining almost exactly 300 points over the previous five days. Then on Thursday the index took a nosedive after Republican Speaker of the House John Boehner held a press conference in which he voiced his disdain about how President Obama was handling the fiscal cliff negotiations. At its low point on Thursday, the Dow had fallen more than 90 points, but managed to close the day down slightly more than 71 points.

On Friday, it seemed as if investors finally began to realize that politicians might not come to a compromise and the economy may fall off the cliff and back into a recession. For the second day in a row, investors were greeted with positive economic data in the morning, but the markets still closed down for the day. Yesterday, the Dow lost another 35 points and managed to end the week down 19 points or 0.14%.

After another wild roller-coaster ride for market participants this week, 14 of the Dow's 30 components ended the week in the red.

But before we get to this week's big losers, I would like to point out that Hewlett-Packard (HPQ 0.69%) was the Dow's big winner this week. Shares of the PC company moved higher by 6.49%. The main catalyst for the move higher came early in the week, when rumors were floating around that activist investor Carl Icahn was looking at the stock. While the idea of Icahn moving into the stock is not totally out of the realm  of possibility, given his history with Yahoo! and other high-profile technology stocks in the past.

Now to this week's losers
The biggest Dow loser this week was Wal-Mart (WMT 0.46%), which saw its shares drop 4.61%. CEO Mike Duke stated his concerns this week about the fiscal cliff and how the uncertainty is affecting consumer spending. He said 15% of Wal-Mart's customers have indicated they are cutting back on holiday spending because of the fiscal cliff.  On Wednesday, meanwhile, news broke that Wal-Mart was in talks to purchase the controlling stake of the Turkish retailer Migros. The deal was believed to value Migros at $4 billion. Shares of Wal-Mart were down 1.79% on Wednesday alone.

Shares of United Technologies (RTX 0.84%) ended the week lower by 1.24%. The Pentagon announced this week that it will pay 4% less for each F-35 jet it buys from Lockhead Martin and is said to be negating a separate agreement with Pratt & Whitney, a subsidiary of United Technologies. Since the government is purchasing the plan at a reduced rate, it is likely the engines for the F-35, which are made by Pratt & Whitney, will probably be sold at a discount.  

And for the second week in a row, shares of Disney (DIS 0.16%) moved lower. Shares slid 1.09% after a fall of 1.06% during the prior week. Two weeks ago, shares moved lower primarily because the stock went ex-dividend. This week there was very little negative news pertaining to the company, but the share price has pulled back from its 52-week high, so some shareholders may just be selling shares at what they feel is the high point.

Another Dow component that recently hit new 52-week highs and pulled back this week on very little news is Home Depot (HD 0.74%). The company was the runner-up in the Dow's Biggest Loser contest this week, as shares of the do-it-yourself home improvement store lost 3.54% during the past five days.

Last week, Coca-Cola (KO 2.14%) lost 0.5% of its value, and while the company again managed to make the loser's list, shares were down only 0.1% this week. There were other mild drops at Bank of America (BAC 3.35%), American Express (AXP 6.22%), and IBM (IBM 0.06%), which saw their shares drop 0.18%, 0.03% and 0.21%, respectively.

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