This Week's Top Gainers and Laggards

As earnings season kicks off, the brief bear market the S&P 500 fell into earlier this month is a fading memory. Heading into Friday's trading, the S&P 500 was up 4.2% on the week and was up 6.4% in October. Friday closed out the week on an especially strong note; the S&P soared 1.74%.

Earnings are a key contributing factor. While Alcoa (NYS: AA) opened up earnings season with a thud, Google (NAS: GOOG) closed the week on a strong note. Analysts had pegged Google at flat sequential earnings growth, but it managed to grow its bottom line by 11% over last quarter. Google's gains poured even more fuel into the IT sector's gains; through Thursday it was already the week's top-gaining sector.

Here's a look at which sectors saw the highest -- and lowest -- gains through last Thursday in a generally upbeat market.

Top 3 Performing Sectors

Bottom 3 Performing Sectors

Source: S&P Capital IQ. Data as of Oct. 13 price change. Monthly price change is Sept. 30 to Oct. 13.

Drilling down on individual stocks, Sprint Nextel (NYS: S) saw the highest returns. However, it'd be deceptive to look at Sprint's returns last week in isolation; in the preceding week Sprint saw its shares hammered when it unveiled network-upgrade plans without an accompanying clear outlook to investors how it'd fund building out its next-generation LTE network. Its shares popped back this week as more clarity was given on how Sprint could avoid a "funding gap," but its shares are still down 8.6% for the month, making it the second-worst performer in the S&P 500 this month.

This Week's Top 3 Performing S&P 500 Companies

Source: S&P Capital IQ. Data as of Oct, 13 price change.

On the short end of the stick last week we find First Solar (NAS: FSLR) , which also happens to also be the worst-performing S&P 500 stock in October. A continued fall in the price of solar modules throughout the year is crushing results across the industry, but First Solar saw especially bad results this week, thanks to a particularly harsh analyst downgrade.

Also making the S&P's worst-performer list were PG&E (NYS: PCG) and Textron (NYS: TXT) , though neither company had any particularly negative news this week.

Bottom 3 Performing S&P 500 Companies

Source: S&P Capital IQ. Data as of Oct. 13 price change.

Looking ahead to this week, we find a number of high-profile companies are set to report. One of the more interesting will be Apple (NAS: AAPL) , which will release its quarterly results Tuesday after the bell.

Analysts are expecting $7.29 in earnings per share on $29.45 billion in sales, but they'll be wrong. Even with many consumers holding out on buying a new iPhone this summer while rumors swirled that the next iPhone was just around the corner, Apple will almost surely see a quarter-over-quarter rise in iPhone sales. Anything less than $32 billion in sales and $8 in earnings per share will probably be a disappointment, and Apple is likely to beat both targets.

That's it for our recap of this week's biggest gainers and laggards. To stay updated on any of the companies listed above, add them to your Watchlist by clicking the "+" sign next to the respective tickers. Don't have a Watchlist yet? You can start one for free

At the time thisarticle was published Eric Bleeker owns shares of no companies listed above. The Motley Fool owns shares of First Solar, Denbury Resources, Apple, Textron, and Google. Motley Fool newsletter services have recommended buying shares of Google, First Solar, and Apple and creating a bull call spread position in Apple. Try any of our Foolish newsletter services free 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 a disclosure policy.

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