BOSTON (TheStreet) -- U.S. stock-market indices have been rebounding from July's lows as the American economy slowly recovers from the worst recession since World War II.

The Dow Jones Industrial Average, Nasdaq and S&P 500 are on track to deliver their best quarterly performances in a year, with wide swings that have tested investors' nerves. The Dow, the blue-chip benchmark, has gained 11% this quarter through yesterday, helping it to almost erase its second-quarter losses. The S&P 500 has advanced 2.8% this year, slowing from last year's pace. The technology-heavy Nasdaq is up 13% this month.

Here are the 10 best-performing stocks of the S&P 500 this year, so far.

10. Titanium Metals ( TIE)

Shares of this Dallas supplier of titanium parts have jumped 88% over the past 12 months.

Titanium Metals is benefiting from renewed demand from aerospace customers. The company doubled its second-quarter profit to $19 million, or 11 cents a share, as revenue grew 3% to $212 million. Demand last year shrank as companies cut production of planes and other products. The situation has since reversed, and Titanium Metals CEO Bobby O'Brien said earlier this year that he expects sales to increase in 2010.

D.A. Davidson rates the stock "buy" and expects the shares to climb 20%, to $23, over 12 months.

9. Huntington Bancshares ( HBAN)

In the first quarter, this Columbus, Ohio, bank reported its first profit in more than a year, exceeding analysts' estimates with a profit of $40 million. In the second quarter, Huntington Bancshares beat expectations again with a profit of $48.8 million, or 3 cents a shares, after a year-earlier loss. Analysts had predicted a loss. Earlier this month, Sanford Bernstein and Raymond James boosted their ratings on the stock. Though almost half of the analysts who follow the stock rate it "hold," Stifel Nicolaus rates the company "buy" and says shares could rise 60%, to $9, during the next year.

8. Priceline.com ( PCLN)

This Norfolk, Conn.-based travel-booking Web site is best known for its online-auction process, but it's benefitting most from the second-quarter acquisition of TravelJigsaw, an international car service. The deal helped the company, fronted by William Shatner, boost bookings by $43.9 million in the second quarter. Priceline is also gaining from international bookings, which grew three times faster than domestic bookings. The company forecast this trend to continue this quarter, with revenue increasing as much as 34% and profit as much as 48%. Three-quarters of analysts who track the stock rate it "buy." Citigroup said the shares could advance 25% to $425 during the next 12 months.

7. Family Dollar ( FDO)

A weak economy has created opportunities for Family Dollar, the discount-variety-store chain. The Matthews, N.C.-based company has increased earnings more than 10% for the past nine quarters. Family Dollar sales at stores open at least a year rose 6.1% during the quarter that ended in August, when the company opened 75 new stores. CEO Howard Levine said his store chain has spent the past year improving its merchandise and expanding its hours. Half of analysts who track the company rate it "buy," including Barclays, which says the stock could rise 20% to $52, over 12 months.

6. Zions Bancorp ( ZION)

Salt Lake City's Zions Bancorp is the best-performing stock in the 80-member S&P Financials Index this year. The company has been struggling to return to profitability, reporting an 84-cent loss in the second quarter compared with the 52-cent loss analysts had expected. Zions, which has more than 500 banking offices in 10 states, has taken steps to shore up its balance sheet. Two-thirds of the 27 analysts who follow the company rate its shares "hold," but Cantor Fitzgerald rates the stock "buy" and says it could rise 59% to $32 during the next 12 months.

5. Salesforce.com ( CRM)

Like many companies hatched in the late 1990s, Salesforce.com was started in a San Francisco apartment. The company has been using social-networking tools to draw new subscribers to its online client-management service, adding 30% more customers in the quarter ended in July. The company has increased annual sales by 34%, on average, during the past five years. Salesforce expects to boost revenue as much as 23% in its current fiscal year. More than half of analysts who follow the stock rate it "buy." Kaufman Bros. has set a 12-month price target of $140, suggesting the shares could rise 19%.

4. Lexmark ( LXK)

Shares of printer maker Lexmark have gained 3.4% annually, on average, during the past three years, outperforming those of rivals Xerox ( XRX), Hewlett-Packard ( HPQ), Eastman Kodak ( EK) and Canon ( CAJ).

Lexington, Ky.-based Lexmark, led by CEO Paul Curlander, has been expanding its profit margins by cutting expenses and boosting demand in key product areas, such as printer supplies. Analysts are divided over the stock, with 43% considering it a "buy" and 36% rating it "hold." Citigroup says the shares could climb as high as 31% to $55 during the next year.

3. Citrix Systems ( CTXS)

Citrix Systems' software, which allows customers to use fewer servers and operate software remotely, has been gaining popularity as more companies rely on offsite workers. The Santa Clara, Calif.-based company increased revenue 17% in the second quarter from a year earlier, helped by rapidly growing demand in Asia. The stock has jumped 89% in the past year, and many analysts think the shares might have peaked. While one-third of analysts rate the stock "buy," two-thirds rate it "hold." Still, Lazard has set a 12-month price target of $80, which is a 17% gain.

2. Cummins ( CMI)

Cummins, a Columbus, Ind., maker of engines and engine parts, has been a hot pick among investors looking to tap industrial markets in developing countries. The shares have jumped 92% in the past 12 months. In the second quarter, earnings increased almost fivefold to $246 million, or $1.25 a share, as the company increased sales 32% to $3.2 billion. Cummins raised its quarterly dividend by 50% and had its credit rating increased by Standard & Poor's. Analysts are bullish with 10, or 59%, of those following the stock rating it "buy" and seven rating it "hold." Goldman Sachs values Cummins stock at $104; it closed July 15 at $88.31.

1. Akamai Technologies ( AKAM)

Akamai Technologies' software makes Web sites and online video run faster. As cloud computing and video streaming become more common for Internet users, the Cambridge, Mass., company is positioned to benefit. Its shares have doubled this year. The company has met or beat analysts' estimates in each of the past four quarters. This quarter, Akamai expects to earn 32 to 34 cents a share, excluding some items. Revenue is forecast to increase as much as 22% to $252 million.

Although two-thirds of analysts who follow the stock rate it "hold," Goldman Sachs rates it "buy" and says the shares could rise 19%, to $60, during the next year.

>>>To see these stocks in action, visit the 10 Top-Performing S&P 500 Stocks portfolio on Stockpickr.

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