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.

The Dow Jones Industrial Average (DJINDICES:^DJI) closed today up 46 points, or 0.31%, and finished the week at 15,010. That's still down 70 points, or 0.47%, for the week, but at least the index manged to fight off the bears yesterday and today to close out the week on a two-day winning streak. Both the S&P 500 and the Nasdaq also managed to make today a winning session, as they increased by 0.39% and 0.52%, respectively.

Today's positive moves came despite some terrible numbers for the housing industry and may thus be a sign that the market believes the data will be enough to keep the Federal Reserve from beginning to taper its bond buying at the September meeting. The housing report indicated that the number of homes sold in July came in at 394,000, down from the revised number of 455,000 sold in June, and well below the 485,000 Wall Street was expecting. The decline could have been caused by a number of factors, such as weather, rising housing prices, or even the rapid jump in interest rates over the past few weeks. Whatever the reason, the housing recovery is probably slowing, and the health of the economy may not be as good as many believed it was.

Now let's look at a few of the other drags on the Dow today, as we review the index's biggest decliners of the session.

Despite winning a No. 1 ranking in customer satisfaction for the seventh year in a row, American Express (NYSE:AXP) slid 0.28% today. The survey by J.D. Power looked at six categories to determine the top credit card -- customer interaction, billing and payment process, credit card terms, rewards programs, benefits and services, and problem resolution. A company spokesperson said American Express is honored to once again be the top card but that the company takes these matters seriously and continuously strives to improve in every area.  

Cisco Systems (NASDAQ:CSCO) was the Dow's worst-performing stock of the day, as shares fell 0.62%, followed by Travelers (NYSE:TRV), which lost 0.45% of its value. Very little news pertaining to either company came out today.

Despite trading higher at times today, shares of Cisco took a big slide late in the day as trading volume spiked with about 10 minutes left in the session. More than 3 million shares traded hands at 3:50 p.m. ET, more than three times the volume of any other minute of the day, and volume remained elevated for the final minutes of the session. With just slightly higher activity overall than normal -- 41 million shares traded hands, while the three-month average is 35 million shares -- the spike at the end of the day probably indicates that a large investment firm was dumping shares and perhaps even closing out a position. If that was the case, investors don't need to worry right now, as the fundamentals of the business certainly didn't change this afternoon.

As for Travelers, we're now getting close to peak time for the 2013 Atlantic hurricane season, which the National Oceanic Atmospheric Administration believes will bring six to nine hurricanes. Investors may be paring back their exposure as potential weather problems could cost the company millions, if not billions, in claims and hurt profits.

Fool contributor Matt Thalman has no position in any stocks mentioned. 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

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