The Dow Jones Industrial Average (INDEX: ^DJI) fell 0.69% today, its worst one-day performance so far in 2012.

Investors had thought the worst was behind them, since Greece's political leaders had (finally!) agreed to even more incredibly unpopular and economically counterproductive austerity measures. But European finance ministers aren't taking any chances. They want the latest bloodletting measures to pass Greece's parliament before they agree to release any more bailout cash.

No bailout, financial chaos. Hence, the market decline.

These were the three worst performers:


Price Change

Alcoa (NYSE: AA) (3.3%)
DuPont (NYSE: DD) (1.8%)
Hewlett-Packard (NYSE: HPQ) (1.4%)

Why, you may ask, did shares of these three companies decline?

As one of the more volatile and economically sensitive members of the Dow, shares of Alcoa have been acting like a leveraged bet on the overall stock market lately. Moreover, a fresh report by Reuters came out predicting a bearish aluminum market. Rival Rio Tinto reported a 59% profit decline after it had to mark down assets of a 2007 acquisition of Canadian aluminum maker Alcan. And Bloomberg reports that aluminum traders probably closed out their bullish bets on aluminum. All in all, not a great combination of events for Alcoa.

DuPont is in the news after the U.S. Justice Department accused several people with stealing DuPont's titanium oxide trade secrets for China. The charges could complicate relations with China, on which DuPont has become increasingly reliant as it ramps up its manufacturing capacity there.

Hey, it had to be someone. As one of the better performing Dow stocks so far this year, it was Hewlett-Packard's turn to have the stock market equivalent of a bad hair day. We also saw this happen today with Bank of America (NYSE: BAC), the Dow's best-performing stock so far this year, which was the fourth-worst-performing stock today despite coming to a long-awaited settlement with the attorneys general of 49 states just yesterday over wide-ranging fraud allegations. Sometimes stocks just take a breather.

Alcoa, DuPont, and Hewlett-Packard were the worst performers in a down day, but it's important for us to remember that it's long-term performance -- not daily price fluctuations -- that ultimately matter for investor returns. If you're interested in one stock that our chief investment officer picked to crush the market, check out our brand new report, "The Motley Fool's Top Stock for 2012." It highlights a company that is revolutionizing commerce in Latin America. For a limited time, you can get instant access to the name of this company by clicking here -- it's free.

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