The top after-market NYSE losers on Thursday are: Ruby Tuesday, Royal Bank Scotland Group, Olin, Hypercom, Hypercom, Kansas City Southern and PetroChina Co.

Ruby Tuesday, Inc. (NYSE:RT) shares slumped 11.31 percent to $9.8 in aftermarket trading session. The company reported fourth quarter net income of $13.92 million or $0.21 per share compared to $20.97 million or $0.33 per share in the same quarter last year.

For the first quarter, the company expects earnings to be in a range of $0.03 to $0.06 per share against analysts’ expectation of $0.20 per share. The company also expects fiscal 2012 earnings to be in a range of $0.75 to $0.85 per share, while analysts’ expect earnings per share of $0.97.

Royal Bank Scotland Group Plc (NYSE:RBS) shares plunged 6.86 percent in aftermarket trading session. The company stock surged more than 7 percent in regular trading session.

Olin Corp. (NYSE:OLN) shares plunged 5.01 percent to $21.80 in post market trading session as its third quarter earnings forecast fell short of analysts’ expectations. The company expects third quarter earnings to be in a range of $0.50 to $0.55 per share against analysts’ estimation of $0.69 per share.

Its second quarter net income rose to $42.1 million or $0.52 per share from $16.9 million or $0.21 per share in the same period last year.

Hypercom Corp. (NYSE:HYC) shares declined 4.26 percent to $8.55 in post market trading session.

C.R. Bard, Inc. (NYSE:BCR) shares declined 3.38 percent to $108.9 in post market trading session. The company swung to second quarter net loss of $47.80 million or $0.55 per share compared to net income of $124.60 million or $1.29 per share in the same quarter a year-ago.

Kansas City Southern (NYSE:KSU) shares declined 2.72 percent to $59.70 in post market trading session. The company reported second quarter net income of $70.7 million or $0.64 per share compared to $34.6 million or $0.34 per share in the same quarter last year.

PetroChina Co. Ltd. (NYSE:PTR) shares declined 2.57 percent to $146.10 in post market trading session. The stock has a 52 week low of $103.39 and 52 week high of $158.83 and has $274.28 billion market capitalization.

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