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 major U.S. indices started today on a four-day winning streak, with the Dow Jones Industrial Average (Index: ^DJI) coming off a 193-point rise yesterday. New Federal Reserve chief Janet Yellen's testimony on Capitol Hill seemed to impress Wall Street as she essentially told lawmakers the central bank would maintain current monetary policies and not much would likely change under her leadership.

But today it seems investors aren't convinced this rally has legs, and some are taking profits. As of 1 p.m. EST, the Dow is off by 34 points, or 0.21%, the S&P 500 is flat, and the Nasdaq is up 0.21%.

One big winner today within the Dow is Caterpillar (CAT -0.11%), as shares are up 1.1%. The move is unlikely the result of any specific news, but more probably a number of factors shining favorably for the company. One such shiny factor is gold and other precious metals, which have been rising in price since the start of 2014. As a rather difficult 2013 for gold, the price has stabilized -- a sign for emerging markets to begin production or start new operations, which will certainly require heavy machinery of the type made by Caterpillar. Another positive for Caterpillar today is a report that China's exports increased by 10.6% in January. This may indicate that the world's second largest economy is growing faster than some expected and that new construction and development projects are coming, again an area were heavy machinery is needed.

One big Dow loser today is Procter & Gamble (PG 0.86%), as shares are down more than 1.7%. The drop comes after management lowered its sales forecast for 2014. The company believes that unfavorable currency exchange rates will negatively impact sales and earnings. Nations that analysts would say are of concern include Venezuela, Argentina, Turkey, South Africa, Russia, Ukraine, and Brazil. These are for the most part big emerging market economies that should help the company grow, when it's not dealing with currency problems that make endeavors into new regions a risky bet.  

One big mover outside the Dow is Amazon.com (AMZN -1.14%), as shares are off by slightly more than 3.5%. The drop comes after a UBS analyst downgraded the stock based on the company's idea of raising the price of its Amazon Prime membership. The analyst cited a survey which indicated that the company would lose members if it increases the Prime membership fee. The proposed price increase comes as shipping costs are rising and Amazon is offering more with its streaming service, but the analyst and others question whether the company can get away with a possible $35 increase and justify a new $119 rate with customers. Investors shouldn't panic at this point, but keep an eye on what happens.

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