Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

After the terrible week that the Dow Jones Industrial Average (^DJI -0.98%) has had, even the release of two important economic data points wasn't enough to budge the index in one direction or the other. The two reports were the preliminary consumer sentiment data, which came in lower than expected, and slightly lower than last month's reading, and the housing starts data from July, which rose 6% for the month.

But, those releases weren't enough to push the markets in any real direction and, for the most part, the major indexes remained rather flat for the session. The Dow closed the day down 30 points, or 0.2% and now sits at 15,081. The S&P 500 lost 0.33%, while the Nasdaq slid lower by 0.09%. Only 11 of the Dow's 30 components managed to stay out of the red today, which means there were 19 that traded lower. Let's take a quick look at a few of the losers.

Pfizer (PFE -3.85%) was one of the big losers on the Dow today, as shares dropped 1.49%. The most likely reason for the decline was the announcement that the U.K.'s National Institute for Health and Care Excellence has recommended against using Pfizer's lung cancer drug Xalkori, because of the high cost. As my colleague Dan Carroll noted earlier today, Xalkori is a small drug for Pfizer at this time, but had the potential to bring in $2.5 billion in revenue before this announcement, which would really help the company overcome its loss of revenue due to patent expirations. 

This afternoon, I explained the likely cause of Verizon's shares moving lower -- possible problems entering the Canadian telecommunication market. The same problems that Verizon is likely going to face in Canada are issues that AT&T (T -1.37%) would also face if it were to attempt to open operations in the north. AT&T is currently the No. 2 telecom company in the U.S., and if it ever wants to realize healthy growth rates, it will have to pursue opportunities in other countries. But, any country that AT&T wants to go into will surely already have a number of well-established operators that are not just going to roll over and give up market share to the U.S. giant without a fight. That means that it would cost AT&T a lot of time and money to establish itself in a new market, which could hurt the company's overall profits for a time while the new area is being developed.

Shares of Cisco (CSCO -0.52%) slid lower again today, losing 0.88% of their value, ending a terrible week for the company in which it lost 6.83% over the last five trading sessions. Today, the stock likely fell because of the overall netgative sentiment toward the company since its earnings report earlier in the week, when it lowered its guidance for the remainder of 2013. Furthermore, Cisco announced that it was laying off 5% of its workforce in an effort to lower its costs, because enough revenues weren't coming in to justify the extra staff. But, my colleague Rick Munarriz posed a great question today, "How does Cisco expect to pick up the pace of its growth with 4,000 fewer employees around?" I must agree with Rick, and am wondering how a company intends to grow its revenue and product offerings while reducing the staff that could help make more product and higher sales.

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