Traders work on the floor of the New York Stock Exchange on May 1, 2012.
Traders work on the floor of the New York Stock Exchange. REUTERS

The top after-market NYSE gainers Wednesday were NRG Energy Inc, EMC Corporation, Juniper Networks Inc and SM Energy Company.

NRG Energy Inc (NTG) shares climbed 2.03 percent to $20.07 in post-market trading. The stock has a 52-week low of $14.29, a 52-week high of $23.78 and $4.49 billion in market capitalization.

EMC Corporation (EMC) shares gained 2.01 percent to $24.39 in post-market trading. The stock has a 52-week low of $21.25, a 52-week high of $30 and $50.37 billion in market capitalization.

Juniper Networks Inc (JNPR) shares advanced 1.96 percent to $17.69 in post-market trading. The stock has a 52-week low of $14.01, a 52-week high of $25.04 and $8.95 billion in market capitalization.

SM Energy Company (SM) shares rose 1.92 percent to $53.59 in post-market trading. The stock has a 52-week low of $39.44, a 52-week high of $87.09 and $3.47 billion in market capitalization.

The top after-market NYSE losers Wednesday were HCA Holdings Inc, EnergySolutions Inc, Spectra Energy Partners LP, International Paper Company and Iamgold Corporation.

HCA Holdings Inc (HCA) shares declined 4.95 percent to $30.12 in post-market trading. The stock has a 52-week low of $19.86, a 52-week high of $34.32 and $13.99 billion in market capitalization.

EnergySolutions Inc (ES) shares slumped 4.61 percent to $3.31 in post-market trading. The stock has a 52-week low of $1.43, a 52-week high of $5.43 and $312.28 million in market capitalization.

Spectra Energy Partners LP (SEP) shares dropped 4.51 percent to $27.31 in post-market trading. The stock has a 52-week low of $28.30, a 52-week high of $33.27 and $2.76 billion in market capitalization.

International Paper Company (IP) shares fell 4.16 percent to $32.93 in post-market trading. The stock has a 52-week low of $25.36, a 52-week high of $38.42 and $15.09 billion in market capitalization.

Iamgold Corporation (IAG) shares declined 3.10 percent to $14.40 in post-market trading. The stock has a 52-week low of $9.20, a 52-week high of $21.38 and $5.59 billion in market capitalization.

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