Although we are now in the thick of earnings season, upgrades and downgrades seemed to move stocks more than quarterly results today. However, the Dow Jones Industrial Average (^DJI 0.51%) managed to post a winning session as the other major indexes fell.

The Dow closed higher by 18 points, or 0.14%, and now rests at 13,507. The S&P 500 (^GSPC 1.10%) closed down 1.37 points, or 0.09%, while the NASDAQ (^IXIC 1.50%) lost eight points or 0.26%.

Of the Dow's 30 components, 13 of them ended the trading day in the red. This afternoon, I explained why three of the biggest Dow losers were JPMorgan Chase (JPM 1.07%), Bank of America (BAC 1.42%), and Verizon (VZ 3.06%). To read about what negative news helped push these companies lower, click here, or stick around to learn about the outside forces affecting the stock prices of Caterpillar (CAT 2.07%), IBM(IBM 1.10%), and Hewlett-Packard (HPQ 0.25%).

So what happened?
Shares of Caterpillar lost 0.59% today. The move lower may be related to industrial production falling in Europe during November. The European Union's statistical office announced today that overall industrial production for November was lower than for October by 0.3%. That comes after October's production had fallen 0.8% in the EU. Production numbers more closely relating to Caterpillar, the manufacturing of durable goods, fell by 1.4% in the EU and 1.1% in the Eurozone during November. Durable goods production in the EU over the past 12 months is down 6.8%.  

Shares of IBM ended the trading down lower by 0.94% after it was downgraded by JPMorgan Chase analyst Mark Moskowitz. IBM was reduced to a neutral rating from a previous overweight mark. The rating change came because Moskowitz believes IBM will fall out of investors' favor due to riskier bets in the IT world.

Moskowitz also upgraded Hewlett-Packard (HPQ 0.25%) from underweight to neutral and believes both Hewlett-Packard and Dell should be kept on investors' watch lists. Both PC companies had a wonderful day as their shares gained 3.68% and 12.96%, respectively. Dell also received a boost after rumors began swirling that it would be purchased and taken private by a private equity firm.  

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