The top after-market NYSE losers on Tuesday are: Ion Geophysical, Boston Beer Co, HFF, Orbitz Worldwide, Emdeon, Buckeye Technologies, Calgon Carbon, Arcos Dorados Holdings, Thor Industries and MetroPCS Communications.

Ion Geophysical Corp. (NYSE:IO) shares slumped 11.16 percent to $8.52 in post market trading session. The company reported second quarter net income of $2.56 million or $0.02 per share compared to $1.07 million or $0.01 per share in the same quarter last year and against analysts’ estimation of $0.04 per share.

Boston Beer Co, Inc. (NYSE:SAM) shares slumped 8.11 percent to $81.50 in post market trading session after lowering full year guidance. For the fiscal 2011, the company lowered its full year earrings guidance to a range of $3.20 and $3.60 from earlier estimation of $3.45 and $3.95 per share.

The company reported second quarter net income of $28.0 million or $2.01 per share from $16.3 million or $1.13 per share in the same period a year-ago.

HFF, Inc. (NYSE:HF) shares plunged 7.98 percent to $13.26 in aftermarket trading session. The company announced that it has filed a preliminary prospectus supplement with the Securities and Exchange Commission for a proposed underwritten public offering of about 4.05 million shares of its Class A common stock.

Orbitz Worldwide, Inc. (NYSE:OWW) shares plunged 7.35 percent to $2.90 in aftermarket trading session.

Emdeon Inc. (NYSE:EM) shares plunged 5.74 percent to $14.13 in post market trading session. The stock has a 52 week low of $9.95 and 52 week high of $17.45 and has $1.74 billion market capitalization.

Buckeye Technologies, Inc. (NYSE:BKI) shares declined 5.27 percent to $25.00 in post market trading session. Its fourth quarter net profit rose to $14.10 million or $0.35 per share from $9.72 million or $0.24 per share in the same quarter a year-ago.

Calgon Carbon Corp. (NYSE:CCC) shares declined 4.99 percent to $15.04 in post market trading session. The company reported second quarter net income of $11.3 million or $0.20 per share from $2.9 million or $0.5 per share in the same quarter last year.

Arcos Dorados Holdings Inc. (NYSE:ARCO) shares declined 4.06 percent to $24.11 in post market trading session. Its second quarter net income rose to $14.2 million or $0.07 per share from $13.5 million or $0.06 per share in the same period last year.

Thor Industries, Inc. (NYSE:THO) shares declined 4.06 percent to $21.75 in post market trading session. The company announced preliminary sales and backlog for the quarter and twelve months ended July 31, 2011. Preliminary sales for the quarter rose 16 percent to $769 million from $664 million last year.

MetroPCS Communications, Inc. (NYSE:PCS) shares declined 3.46 percent to $10.17 in post market trading session. The company stock plunged more than 35 percent in regular trading session as its second quarter earnings fell short of expectations. The company reported second quarter net income of $0.23 per share compared to $0.22 per share in the same quarter last year and against analysts’ estimation of $0.28 per share.

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