Although this past week was slightly shorter than most due to the long holiday weekend, it was still filled with drama and excitement. The Dow Jones Industrial Average (^DJI -0.12%) opened sharply higher on Tuesday, and managed to close up 106 points for the day, but on Wednesday, the blue chip index closed lower by 106 points. Thursday seemed like it would be a good day until just after 2:56 p.m. EDT, at which point the Dow began its 73-point decline before closing up just 21 points for the day. Then Friday came along, and while the decline didn't come till late afternoon, the day started  with the Dow flat, but the fall lasted nearly two hours. When all was said and done, the index had lost 208 points on the last day of the week. 

All in all, the Dow Jones lost 187 points, or 1.22%, this past week, while the other major indexes also closed out the last week of May on a down note. The S&P 500 declined by 1.16%, and the Nasdaq slid lower by just 3.23 points, or 0.09%.

Before we hit the Dow losers, let's look at the big winner of the week --Bank of America (BAC 1.59%). The Wall Street bank saw shares rise 3.17% during the short trading week despite the continued Countrywide problems hanging around its neck. One reason why shares may have increased this past week is rising interest rates. Although the bank has been able to borrow funds cheaply for some time because interest and mortgage rates were also being held down, the spread between what B of A borrows at, and then lends at, has been low. Now that rates are climbing higher, the spread is widening, which means that the bank will make a larger profit on basic banking transactions that carry low risk compared to what the Wall Street firms were doing just a few years ago.

The big loser's
Pfizer (PFE -1.05%) lost 6.23% this past week, with the largest one-day decline coming on Friday after the stock was hit with a trifecta of problems. First, the health-care industry had a rough day, in general, led by UnitedHealth, which lost 3.14% during the regular trading session during the day. Second, the stock was given a 12-month price target of $27 per share by an analyst at SunTrust. And lastly, rising interest rates is having a negative effect on stable high yielding blue-chip stocks, as investors leave riskier equities in favor of risk-free Treasury bonds, which are currently paying nearly identical yields as the Pfizer's 3.3% dividend. The interest-rate pressure was a running theme within the Dow this week, as all three of the top losers likely experienced investors bailing on stable stocks in favor of the "safety" of bonds.

The biggest Dow loser this week was consumer facing, slow growing, blue-chip stalwart Procter & Gamble (PG 0.65%). Shares of P&G had risen the first four weeks of May, but the streak abruptly came to an end this past week with shares losing 6.25% over the past four trading sessions. That is also the largest one week decline the stock has seen in 2013, slightly beating the 5.31% decline the stock experienced the last week of April after the company reported lower-than-expected first-quarter revenue, and management lowered its forecast for the remainder of the year.

This week's decline was likely caused by a number of different factors all playing on the stock. Last week, we saw shares increase after the announcement that former CEO A. G. Laffley would be returning. A few of my colleagues have pointed out this week that the increase on Laffley's back was likely an overreaction, and shares could be declining as short-term investors take profits. Additionally, this past week, The Wall Street Journal reported that Laffley was quick at work and already making big managerial changes to the company's corporate structure. P&G will soon be broken into four operating divisions, with each having its own head, who will report directly to Laffley. While it's unknown at this time if this will increase corporate cost, it's likely a safe bet to assume it will, while also increasing competition within the company. This is something that can be both constructive and destructive depending on the atmosphere.

Shares of Coca-Cola (KO 0.78%) also traded lower this past week by 5.32%. The company is currently facing a number of headwinds, which are not only slowing the company's growth, but pushing the stock price lower. This past week, we saw slower-than-expected GDP growth in China, which is an important market for the soft-drink company, especially since it is having issues in other markets around the world. Here at home, the push to lower obesity continues to hurt the company. And in Venezuela, bottling-plant workers are on strike; at this point, the company expects this will lower revenue by at least 15%. 

A few other Dow losers this week:

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