Over the past few days, I have noted a number of times how irrational investors have been lately. Just earlier this week, the Dow Jones Industrial Average (DJINDICES:^DJI) had been on a five-day winning streak, during which time, the index rose a few hundred points. It seemed as if nothing could stop the Dow from rising. Then, yesterday, with 18 days left in the year, and the Speaker of the House John Boehner telling everyone that he was concerned that no compromise was going to save us from falling off the cliff, the Dow was finally stopped.

After the index slid 71 points yesterday, it ended today down another 35 points, or 0.27%. This slide also came on a day when investors were given some decent economic data. Perhaps the mix of the top Republican law maker warning Americans, and the deadline looming just weeks away, was enough to finally wake investors up. Some market participants and politicians also have stated that the markets need to start sliding in order for the politicians to really take this whole thing seriously. Regardless of what causes a deal to be made, the one thing that most investors want to see is a deal.

The Dow currently sits at 13,135, and 19 of the index's 30 components closed the day in the red.

The biggest loser of the day was American Express (NYSE:AXP), which lost 1.85%, after very little negative news was to be found pertaining to the company. Additionally, its fellow Dow financial stocks ended the day on a good note, as JPMorgan Chase (NYSE:JPM) and Bank of America (NYSE:BAC) closed up 0.07% and 0.38%, respectively.

The seconded biggest loser today was Microsoft (NASDAQ:MSFT), which lost 1.11% during today's trading session. The Dow technology stocks were a mixed bag today, as International Business Machines (NYSE:IBM) also ended the day down 0.12%, but Intel (NASDAQ:INTC) and Cisco (NASDAQ:CSCO) both closed higher, up 0.18% and 0.66%, respectively.

Merck (NYSE:MRK) came in to round out the top three losers, as its shares dropped 0.93% today. Pfizer (NYSE:PFE), Merck's fellow Dow pharmaceutical stock, also posted a losing session today, as the stock lost 0.59%.

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Fool contributor Matt Thalman owns shares of Microsoft, Bank of America, and JPMorgan Chase & Co. The Motley Fool owns shares of Bank of America, International Business Machines, Intel, JPMorgan Chase & Co., and Microsoft. Motley Fool newsletter services recommend American Express Company, Cisco Systems, International Business Machines, Intel, and Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.