This was a week that S&P 500 Index (SNPINDEX:^GSPC) investors would do better to forget. Stocks lost nearly 4% on Wednesday and Thursday alone, as Wall Street had a very public panic attack after learning that the Fed won't print exorbitant amounts of money forever and ever. Even after adding four points, or 0.3%, Friday, the index lost more than 2% this week, as it closed at 1,592. But, while today may have marked the end of a temporary nightmare on Wall Street, these companies haven't yet woken up from theirs.

The most visible decliner of the day was Oracle (NYSE:ORCL), the $140 billion software giant. Shares cratered 9.3% Friday after the company posted disappointing sales for its fiscal fourth quarter yesterday. Even more disconcerting is the realization that this marks the second straight quarter of below-par revenue. Oh, the company also authorized doubling its dividend, increasing share buybacks by $12 billion, and plans to start trading on the NYSE. None of that seemed to matter much.

Teradata (NYSE:TDC) shares were hit by Oracle's underwhelming results, as well. Teradata, which slumped 4.2% today, competes with Oracle in several areas, one of them being Big Data -- the growing need for companies to sift through, analyze, and mine vast amounts of data they already have stored or continue to collect. If Oracle's sales miss was truly a reflection of wider economic weaknesses, as the company claims, then Teradata's quarterly revenue might also disappoint when it's announced next month. 

Lastly, shares of Allergan (NYSE:AGN) slid 3.7% Friday on a downgrade from Goldman Sachs. Allergan, which makes pharmaceutical drugs and medical devices, was downgraded from buy to neutral by the investment bank because of valuation concerns. With shares trading at 32 times earnings, and rumors that a generic version of Allergan's Restasis eye drops is in the works, you can't blame investors for selling off the stock today.

Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.

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