Shares of Hudson Highland Group ( HHGP) were among the Nasdaq's worst performers Thursday, plunging 33% after the staffing company cut its 2005 guidance.

Hudson Highland now expects full-year earnings before interest, taxes, depreciation and amortization to be $27 million to $30 million, down from its prior guidance of $30 million to $34 million. The company attributed the lowered guidance to softness in Australia, New Zealand and North America. In Australia, results were hurt by hiring freezes, while the company said New Zealand has been affected by general economic uncertainty amid the recent elections. Hudson Highland said it saw revenue growth in North America but experienced softer-than-expected demand and pricing pressure in the information technology and accounting/finance groups. Shares of Hudson Highland were trading down $8.54 to $17.80.

Investors also were disappointed in guidance from Charles & Colvard ( CTHR - Get Report), sending the company's shares down 31%. The company, which makes a diamond substitute called moissanite, forecast fourth-quarter sales of $11.3 million to $12.2 million, up from $8.7 million a year earlier. For 2006, the company said it plans to shift its marketing focus to help moissanite retailers develop their business, rather than its prior focus to adding new sellers. The company said it is targeting 2006 revenue growth roughly equal to the dollar amount of its 2005 growth, but noted that due to the sales focus shift its growth rate may become more "uneven." Charles & Colvard also declared a 25% stock dividend and announced that it accelerated the vesting of certain stock options. Shares fell $9.66 to $21.45.

Humana ( HUM - Get Report) shares rose 12% after the health insurer predicted a sharp jump in Medicare enrollment and backed its 2006 earnings forecast. The company expects enrollment in its Medicare plans to exceed 1.7 million as of Jan. 1 -- more than triple the 503,000 members at the end of the third quarter. Humana still expects its 2006 ending Medicare membership to be between 1.7 million and 2.2 million for its stand-alone prescription drug plan products, and 900,000 to 1.1 million for its Medicare Advantage plan. The company also continues to project 2006 earnings of at least $2.70 a share. Analysts polled by Thomson First Call have a mean estimate for earnings per share of $2.72. Humana shares were up $5.70 to $54.02.

Bed Bath & Beyond ( BBBY - Get Report) shares sank 12% after the retailer's third-quarter sales and fourth-quarter outlook fell short of expectations. For the quarter ended Nov. 26, the company earned $134.6 million, or 45 cents a share, matching Wall Street's estimate. Revenue rose to $1.45 billion from $1.31 billion, but missed analysts' mean projection of $1.47 billion. In last year's third quarter, Bed Bath & Beyond earned $121.9 million, or 40 cents a share, on revenue of $1.31 billion. For the fourth quarter, the company expects earnings of 64 cents a share. Analysts, on average, had forecast earnings of 66 cents a share. Shares recently changed hands at $36.25, down $4.99.

Shares of Novelis ( NVL) gained 11% after the aluminum products company announced moves to limit its exposure to metal price ceilings. As a result, the company expects it will no longer have metal price ceiling exposure beyond 2006 that exceeds its internal hedge position. Novelis estimated that about 20% of its total volume is subject to contracts with a metal price ceiling, but this volume should drop to 10% by 2007 as a result of the actions. The company also said it is working toward completing its previously announced restatements, and is searching for a new chief financial officer. Novelis shares were up $1.81 to $18.29.

The most actively traded stocks on the NYSE Thursday included Albertsons ( ABS), down $1.59 to $22.51; General Motors ( GM), down 51 cents to $18.54; Maxtor ( MXO), up 5 cents to $6.98; Pfizer ( PFE), down 1 cent to $24.03; Lucent Technologies ( LU), down 3 cents to $2.76; Time Warner ( TWX), up 8 cents to $17.66; Motorola ( MOT), up 20 cents to $23.10; Micron Technology ( MU - Get Report), down 28 cents to $13.86; EMC ( EMC), up 25 cents to $13.92; and Dynegy ( DYN), up 37 cents to $4.97.

Nasdaq's volume leaders were Microsoft ( MSFT), down 18 cents to $26.55; Oracle ( ORCL), up 16 cents to $12.34; Sirius Satellite Radio ( SIRI), up 6 cents to $6.73; Cisco ( CSCO), up 4 cents to $17.25; Intel ( INTC), up 5 cents to $25.93; Research in Motion, up $5.90 to $67.66; JDS Uniphase, unchanged at $2.51; Tibco Software ( TIBX), up 58 cents to $7.88; Biocryst Pharmaceuticals ( BCRX - Get Report), up $1.76 to $16.97; Red Hat ( RHAT), up $1.06 to $27.62; and Novell ( NOVL), unchanged at $9.10.

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