The top after-market NYSE gainers on Monday are: Community Health Systems, KKR & Co, Callon Petroleum, Oxford Industries and New York & Co. The top after-market NYSE losers are: WMS Industries, Safe Bulkers, Alcoa, Dex One Corp and Flagstone Reinsurance.

Gainers

Community Health Systems, Inc. (NYSE:CYH) shares advanced 4.78 percent to $26.08 in after market trading session. Its stock plunged 35.76 percent in regular trading session after Tenet Healthcare Corp. filed a complaint against Community Health Systems for overbilling patients and reaping illicit gains over the years.

KKR & Co. (NYSE:KKR) shares advanced 2.64 percent to $17.86 in pre-market trading session. The stock has a 52 week low of $8.64 and 52 week high of $18.29 and has $11.88 billion market capitalization.

Callon Petroleum Co. (NYSE:CPE) shares advanced 2.12 percent to $7.087 in post market trading session. The company stock plunged 6.59 percent in regular session as Jefferies lowered price target from $7.30 to $7.00 and maintained “hold” rating.

Oxford Industries, Inc. (NYSE:OXM) shares advanced 1.96 percent to $32.19 in post market trading session.

New York & Co, Inc. (NYSE:NWY) gained 1.88 percent to $7.26 in post market trading session. The stock has a 52 week low of $1.67 and 52 week high of $7.50 and has $427.88 million market capitalization.

Losers

WMS Industries Inc. (NYSE:WMS) shares plunged 8.95 percent to $32.98 in post market trading session as its third quarter earnings forecast fell short of expectations. The company expects third quarter earnings to be in the range of $0.40 to $0.42 per share on revenue of $191 million to $193 million, while analysts expected third quarter earnings of $0.51 per share $213.5 million revenue.

Safe Bulkers, Inc. (NYSE:SB) shares slumped 7.45 percent to $8.57 in post market trading session after the company said it plans to offer 5 million shares to the public.

Alcoa Inc. (NYSE:AA) shares declined 2.53 percent to $17.32 in post market trading session after reporting its first quarter sales that missed Street view as the dollar weakened. The New York-based aluminum producer said its first quarter sales grew 22 percent to $5.96 billion, but fell short of analysts' forecast of $6.07 billion. Earnings from continuing operations were $309 million or 27 cents a share, compared to a loss of $194 million or 19 cents a share last year.

Dex One Corp. (NYSE:DEXO) shares declined 3.14 percent to $4.01 in post after market trading session.

Flagstone Reinsurance Holdings S.A. (NYSE:FSR) shares declined 2.81 percent to $8.64 in aftermarket trading session.

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