Nov. 6 (Bloomberg) -- The following companies had unusual price changes in U.S. trading. Stock symbols are in parentheses, and share prices are as of 4 p.m. in New York.

Energy companies slumped as crude oil fell to a 19-month low and natural gas declined for the first day in five. Southwestern Energy Co. (SWN US) slid 11 percent to $32.90. El Paso Corp. (EP US) lost 16 percent to $8.02. Chevron Corp. (CVX US) decreased 6.4 percent to $70.11. Exxon Mobil Corp. (XOM US) retreated 5.1 percent to $69.96.

Activision Blizzard Inc. (ATVI US) rose 9.4 percent, the most since Oct. 28, to $12.01. The video-game maker formed in July when Vivendi SA bought a controlling stake in Activision Inc. said it plans to buy back as much as $1 billion of its stock.

Amazon.com Inc. (AMZN US) fell 9.2 percent to $47.22, the lowest since April 2007. Citigroup Inc. lowered its rating on the world's largest Internet retailer to ``hold'' from ``buy'' because of signs that consumers have further limited spending.

Ambac Financial Group Inc. (ABK US) tumbled 24 percent to $1.52, the lowest since Oct. 9. A credit-rating downgrade of the bond insurance company that has slumped 93 percent this year forced it to post collateral and terminate contracts.

Amdocs Ltd. (DOX US) fell the most since June 2002, losing 18 percent to $19.34. The world's largest billing and customer- service software provider reported fiscal fourth-quarter profit that fell short of the average analyst estimate and forecast first-quarter sales and earnings that trailed analysts' projections.

AnnTaylor Stores Corp. (ANN US) tumbled the most since November 2000, plunging 26 percent to $8.93. The U.S. clothing retailer that targets women 25 to 55 said third-quarter profit will be less than it previously projected because of a ``dramatic deterioration'' in the financial markets and the economy.

Ansys Inc. (ANSS US) rose 8.8 percent, the most since Oct. 13, to $28.86. The software developer forecast profit of at least $1.68 a share this year. That exceeded the average estimate of $1.60 from analysts in a Bloomberg survey.

Big Lots Inc. (BIG US) slumped the most in the Standard & Poor's 500 Index, falling 26 percent to $17.31. The largest U.S. seller of discontinued goods said third-quarter earnings will be ``near or slightly below'' the low end of its forecast after sales missed its projection.

Blackstone Group LP (BX US) fell 12 percent, the most since Oct. 21, to $7.55. The manager of the world's largest buyout fund said it had a third-quarter loss of $502.5 million as the financial crisis eroded the value of its private-equity investments. Results were worse than even the most pessimistic analysts' estimates.

Conseco Inc. (CNO US) jumped the most in the Russell 1000 Index, climbing 19 percent to $2.09. The Carmel, Indiana-based life insurer said it has no need to raise capital.

Continental Resources Inc. (CLR US) fell the most in two weeks, dropping 13 percent to $25.35. The U.S. oil and gas explorer reported third-quarter sales and profit that fell short of analyst estimates. Earnings of 62 cents a share were 19 percent lower than the average projection, according to Bloomberg data.

Developers Diversified Realty Corp. (DDR US) sank 19 percent to $9.23, bringing its two-day decline to 34 percent. The owner and manager of 720 shopping centers yesterday announced the suspension of a $350 million mixed-use project near Detroit.

DryShips Inc. (DRYS US) slid 21 percent to $15.30 for the biggest loss since shares began trading in February 2005. The transporter of commodities including iron ore and coal said it may not be able to pay off its loans.

Other so-called dry-bulk shippers also declined. Eagle Bulk Shipping Inc. (EGLE US) declined 18 percent to $8.25. Genco Shipping & Trading Ltd. (GNK US) fell 18 percent to $17.82. Excel Maritime Carriers Ltd. (EXM US) slipped 12 percent to $11.24. Diana Shipping Inc. (DSX US) dropped 19 percent to $13.96.

FTI Consulting Inc. (FCN US) tumbled the most since January 2004, sliding 26 percent to $43.11. The company, which advises businesses on litigation, bankruptcies and restructuring, reduced its full-year earnings forecast and will delay an initial public offering of its technology business until next year.

Gafisa SA American depositary receipts (GFA US) fell 20 percent, the most in two weeks, to $11.32. Brazil's second- largest real estate developer posted third-quarter profit that trailed analysts' estimates as the economic slowdown and credit crisis cut demand for residences.

Global Crossing Ltd. (GLBC US) rose the most since March 2006, increasing 17 percent to $7.27. The telecommunications provider that survived one of the biggest U.S. corporate bankruptcies told analysts in a conference call that the rest of 2008 will be ``strong.''

Goodyear Tire & Rubber Co. (GT US) dropped the most since the crash of 1987, plunging 18 percent to $7.32. The largest U.S. tiremaker had its credit-rating outlook lowered to ``stable'' from ``positive'' by Standard & Poor's because of falling tire demand.

Hertz Global Holdings Inc. (HTZ US) slid 12 percent to $5.83. The second-largest U.S. rental-car company said third- quarter profit fell 89 percent as businesses and consumers cut back on travel. Hertz said it won't meet its 2008 earnings forecast.

Hot Topic Inc. (HOTT US) jumped 5.5 percent, the most since Oct. 28, to $6.34. The teen clothing and music retailer said in a statement of preliminary results that it earned as much as 17 cents a share in the fiscal third quarter, topping its previous estimate.

LandAmerica Financial Group Inc. (LFG US) dropped 34 percent to $4.75, the lowest level since at least October 1991. The third-biggest U.S. title insurer postponed the release of third- quarter results, saying it needs ``additional time to complete the preparation and review of its financial statements.''

Las Vegas Sands Corp. (LVS US) tumbled 33 percent to $7.85 for the biggest loss since its December 2004 initial public offering. The casino company whose shares fell as much as 95 percent from their October 2007 peak said it may be in default of some loans if it can't raise capital, threatening its ability to keep operating ``as a going concern.''

McDermott International Inc. (MDR US) fell the most in six years, plunging 33 percent to $10.39. The energy-services company that's expanding its nuclear-fuel business reported third-quarter profit that was 47 percent less than the average analyst estimate, according to Bloomberg data.

News Corp. (NWS/A US) slid the most since at least 1994, tumbling 16 percent to $8.26. The media company controlled by Rupert Murdoch cut its fiscal 2009 profit forecast because of shrinking ad sales at its Fox stations and newspapers.

OM Group Inc. (OMG US) gained 14 percent to $22.11, the highest since Oct. 1. The world's largest cobalt producer posted a 48 percent jump in third-quarter profit, boosted by acquisitions, higher metal prices and a tax credit.

SRA International Inc. (SRX US) had the biggest loss since shares began trading in May 2002, plunging 32 percent to $13. The provider of information technology services to the federal government reduced its 2009 earnings forecast, projecting profit of as much as $1.22 a share. Analysts, on average, estimated $1.34, according to a Bloomberg survey.

Syniverse Holdings Inc. (SVR US) sank 44 percent to $9.99 for the biggest loss since February 2005. The provider of technology services to mobile-phone companies was cut to ``neutral'' from ``outperform'' by Robert W. Baird analyst William Power, who cited ``mounting'' revenue disappointment next year.

THQ Inc. (THQI US) dropped 29 percent, the most in six years, to $4.68. The video-game publisher said it will close five studios and cut 250 jobs to reduce costs and focus on fewer, higher-quality titles. The company also lowered its sales and profit forecast for the fiscal year ending in March.

Toyota Motor Corp. American depositary receipts (TM US) fell 17 percent to $67.09 for the steepest decline in 18 years. The world's second-largest automaker forecast the biggest drop in profit in at least 18 years as a global slump cripples auto demand and gains in the yen erode the value of overseas sales.

Other automakers also dropped. General Motors Corp. (GM US) slipped 14 percent to $4.80. Ford Motor Co. (F US) lost 5.3 percent to $1.98. Honda Motor Co. ADRs (HMC US) slumped 15 percent to $22.40. Nissan Motor Co. ADRs (NSANY US) declined 11 percent to $8.57.

Tyco Electronics Ltd. (TEL US) dropped 12 percent to $16.78, the lowest level since being spun off by Tyco International Ltd. in June 2007. The world's biggest maker of electronic connectors said fiscal fourth-quarter profit fell 55 percent on restructuring costs and forecast a ``significant'' drop in sales and earnings this period.

Warnaco Group Inc. (WRC US) lost 31 percent to $17.80 for the biggest slide since February 2003. The maker of Calvin Klein jeans and Speedo swimwear reduced its earnings forecast for the year, predicting profit of as much as $2.65 a share, excluding some items. The company previously expected to earn at least $2.80.

To contact the reporter on this story: Lu Wang in New York at lwang8@bloomberg.net

Last Updated: November 6, 2008 16:42 EST