Shares of

Gevity

(GVHR)

were among the

Nasdaq's

losers Monday, slumping 17% after the human resources company cut its earnings forecast for the year.

The company now sees earnings of at least $1.31 a share, down from an earlier view of $1.43 to $1.47 a share. Analysts polled by Thomson First Call project earnings of $1.44 a share. The company said that not all aspects of its growth strategy, announced at the beginning of this year, are contributing as planned yet.

"We believe that the delay in further growth acceleration is temporary and can primarily be attributed to two initial challenges. The first is in reference to the pricing aspect of our new multi-carrier health benefit choice program; the second is a longer than anticipated sales cycle in the mid-market," Gevity said. Shares were trading down $3.78 to $20.45.

PepsiAmericas

(PAS)

fell 5% after the seller of

PepsiCo

(PEP) - Get Report

products cut its full-year earnings guidance. PepsiAmericas now sees earnings of $1.35 to $1.39 a share, down from an earlier estimate for earnings at the low end of a $1.44 to $1.49 range. Analysts project earnings of $1.44 a share. The company blamed the shortfall on lower-than-expected pricing.

"While we remain satisfied with our rate increases, the package mix continues to have a negative impact on our net pricing," PepsiAmericas said. "Our higher margin single-serve volume has not rebounded to expected levels, despite the launch of Jazz." Shares were trading down $1.18 to $21.38.

Shares of

Premium Standard Farms

(PORK)

jumped 14% after the company agreed to be acquired by

Smithfield Foods

(SFD)

for $693 million in cash and stock. Smithfield will pay the equivalent of $21.35 a share, representing a 20% premium over Friday's closing price of $17.73. Smithfield also agreed to assume about $117 million in debt, bringing the deal's total value to about $810 million. The purchase is expected to close during the first quarter of 2007. Shares of Premium Standard Farms were up $2.50 to $20.23, while Smithfield fell 62 cents, or 2%, to $28.62.

Northern Empire Bancshares

(NREB)

vaulted 19% after the banking company agreed to be acquired by

Sterling Financial

(STSA) - Get Report

for $335 million in cash and stock. Northern Empire shareholders will receive 0.8050 shares of Sterling stock and $2.71 a share in cash. Based on Friday's closing prices, the deal values Northern Empire at $29.31 a share, a premium of 22%. The deal is expected to close during the first half of 2007. Shares of Northern Empire jumped $4.47 to $28.45, while Sterling shares dropped 24 cents to $32.80.

Shares of

Aftermarket Technology

(ATAC)

tumbled 19% after the supply chain company slashed its third-quarter bottom-line projection. The company now sees a loss of 15 cents to 19 cents a share, compared with an earlier view that called for a profit of 38 cents to 43 cents a share. Analysts project earnings of 42 cents a share.

"We certainly did not anticipate this action at the time of our second quarter call and we are disappointed in the setbacks that led us here," Aftermarket said. The company, which also withdrew its full-year guidance, said it will provide an updated 2006 estimate when it reports third-quarter results in October. Shares were trading down $4.10 to $17.07.

NYSE

volume leaders included

Ford

(F) - Get Report

, down 27 cents to $7.75;

First Data

(FDC) - Get Report

, down $3.39 to $41.26;

Motorola

(MOT)

, up 13 cents to $24.98;

Freescale Semiconductor

(FSL)

, up $2.31 to $39.47;

Lucent Technologies

(LU)

, down 3 cents to $2.26;

Time Warner

(TWX)

, up 7 cents to $17.09; and

Nortel Networks

(NT)

, up 2 cents to $2.37.

Nasdaq volume leaders included

Applied Materials

(AMAT) - Get Report

, up 33 cents to $17.53;

Sun Microsystems

(SUNW) - Get Report

, down 8 cents to $5.20;

Oracle

(ORCL) - Get Report

, up 1 cent to $16.34;

Intel

(INTC) - Get Report

, up 4 cents to $19.55;

Microsoft

(MSFT) - Get Report

, down 2 cents to $26.83;

Cisco Systems

(CSCO) - Get Report

, up 11 cents to $22.83; and

Level 3 Communications

(LVLT)

, down 9 cents to $5.01.