As the Federal Open Market Committee meets for the second day of its two-day meeting, investors nervously wait to hear what the central bank plans to do in the future. While we know the Fed is planning to keep interest rates low until unemployment hits at least 6.5%, we don't know how they plan to unwind the quantitative-easing programs or how it will affect the economy.

These concerns have investors selling more than buying today, and the major indexes are all lower because of it. As of 1 p.m. EDT the Dow Jones Industrial Average (DJINDICES:^DJI) is down 0.58%, while the S&P 500 is down 0.56% and the NASDAQ has fallen 0.63%. Let's take a look at a few of the components that are holding back the Dow.

Dow losers
Shares of Caterpillar (NYSE:CAT) are down 1.8% following the announcement that the company's union members in South Milwaukee rejected a deal that would freeze wages for six years but provide job security. The proposed plan was to cap the number of layoff weeks to 14 per year and reduce or eliminate indefinite layoffs caused by declining sales in mining equipment. The rejection is not something shareholders want to see, because the plan would have allowed Caterpillar to better control costs over the six-year contract period.

Alcoa (NYSE:AA) is also seeing its shares fall today after the company reported that it may reduce production due to low aluminum prices. Since the price of aluminum peaked in 2011, its value has dropped more than a third. Many industry experts point to the boom of new aluminum plants in China and a worldwide slowdown of economic activity, which has caused an oversupply of the metal. The proposed plan is to reduce production by another 11%, but up to this point the company has already lowered production by 13%. The additional cut would mean Alcoa would only be running at about 75% of possible capacity, and with the price of aluminum where it is, that means the company would realize revenue of just more than half what it made in 2011. Shares of Alcoa are down 0.8% this afternoon. 

Shares of Merck (NYSE:MRK) are down 2.6% after the company announced earnings that beat expectations on earnings but missed on revenue. Additionally, investors didn't like that the company reduced its full-year 2013 guidance by $0.15 per share. Merck is facing tough competition from generic-drug makers, and whether or not the company can overcome the patent cliff remains to be seen.