Why the S&P 500 Hit 4-Year Highs

The fire has been lit, and European Central Bank president Mario Draghi is fanning the flames. The ECB's plan to purchase the bonds of its member nations on an unlimited basis, as long as they agree to outside fiscal oversight, reinvigorated the broader market and sent the S&P 500 (INDEX: ^GSPC) screaming up 28.68 points (2.04%), to 1432.12 -- a four-year high. Let's take a look at a few of the companies propelling the S&P 500 higher, as well as some of the drags on the index.

Companies that helped the S&P 500
Solar panel maker First Solar (NAS: FSLR) is one of today's brighter stories in more ways than one. Not only did it win a 25 MW contract from Green Infra in India but, with a good portion of its contracts coming from Europe, the ECB's bond-buying plan has investors excited about the possibility of a pick-up in orders, if Europe's situation stops worsening. My Foolish colleague Travis Hoium thinks this run could be just the beginning for First Solar.

Owens-Illinois (NYS: OI) , a global glass container producer, couldn't keep its gains bottled up, either, ending the day up 9%. Earlier in the week, Owens-Illinois announced that a $90 million asbestos settlement against the company had been thrown out, and today, its chief financial officer backed its previous earnings forecast issued in July. With a large presence in Europe, the simple fact that things aren't getting worse is a great sign.

Companies that hindered the S&P 500
I really had to dig deep to find poor performers on a day like today, but Walgreen (NYS: WAG) was a notable exception, down 2%. Walgreen suffered a double-whammy, reporting a worse-than-expected 8.2% drop in August's same-store sales, and announcing that the Defense Department's Tricare health plan will not be allowing 10 million of its members to fill their prescriptions with Express Scripts in Walgreen's pharmacies. With Tricare representing 17% of all prescriptions filled at Walgreen pharmacies last year, this could have very negative implications for both Walgreen and Express Scripts.

Hard-drive maker Seagate Technologies (NYS: STX) had a rough day, as well, dipping nearly 3%, following a two-notch downgrade from Needham & Co. to "hold" from "strong buy." Needham cited slowing demand for its hard drives and storage devices, as well as rising inventory levels, as the reasons for the downgrade. As one final slap in Seagate's face, Needham kept its "strong buy" rating on its rival, Western Digital. Call me a skeptic, but I wouldn't count out Seagate just yet.

Will it keep shining?
Curious as to whether First Solar can keep shining going forward? Find out the answer to this question, and much more, by getting your copy of our latest premium research report on First Solar. This report highlights all of the opportunities and threats that could affect First Solar, without having to worry about the day-to-day fluctuations in the market. Click here to get your copy and claim your investing edge!

The article Why the S&P 500 Hit 4-Year Highs originally appeared on Fool.com.

Fool contributorSean Williamshas no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen nameTMFUltraLong, track every pick he makes under the screen nameTrackUltraLong, and check him out on Twitter, where he goes by the handle@TMFUltraLong.The Motley Fool owns shares of Express Scripts and Western Digital.Motley Fool newsletter serviceshave recommended buying shares of Express Scripts. Try any of our Foolish newsletter servicesfree for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has adisclosure policy.

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