The top after-market NYSE gainers Wednesday were Swift Transportation, Headwaters, Union Pacific, Iamgold and Southwest Airlines Co. The top after-market NYSE losers were Teradyne, Yingli Green Energy, Buckeye Partners, Varian Medical Systems and Vipshop Holdings Ltd.

Gainers

Swift Transportation Co. (NYSE:SWFT) shares rallied 10.46 percent to $11.30 in post-market trading. The company reported the fourth quarter net profit of $0.38 per share on revenue of $922.6 million, up from a net profit of $0.29 per share on revenue of $860.7 million in the same period last year.

Headwaters Inc. (NYSE:HW) shares surged 3.96 percent to $10.50 in post-market trading. The stock has a 52-week low of $2.26, a 52-week high of $10.15 and $718.57 million in market capitalization.

Union Pacific Corp. (NYSE:UNP) shares gained 2.53 percent to $138.78 in post-market trading. The stock has a 52-week low of $104.08, a 52-week high of $136.19 and $63.67 billion in market capitalization.

Iamgold Corp. (NYSE:IAG) shares advanced 2.17 percent to $9.43 in post-market trading. The company stock tumbled more than 15 percent in regular trading.

Southwest Airlines Co. (NYSE:LUV) shares gained 2.02 percent to $11.59 in post-market trading. The stock has a 52-week low of $7.76, a 52-week high of $11.60 and $8.38 billion in market capitalization.

Losers

Teradyne, Inc. (NYSE:TER) shares plunged 4.87 percent to $16.20 in post-market trading. The company swung to the fourth quarter net loss of $16.5 million or $0.09 per share compared to the net profit of $127.3 million or $0.57 per share in the same period last year.

Yingli Green Energy Holding Co. Ltd. (NYSE:YGE) shares plunged 4.71 percent to $2.83 in post-market trading. The stock has a 52-week low of $1.25, a 52-week high of $6.27 and $453.32 million in market capitalization.

Buckeye Partners L.P. (NYSE:BPL) shares declined 4.24 percent to $52.20 in pre-market trading. The company announced Wednesday that it had commenced a public offering of 6,000,000 limited partnership units representing limited partner interests pursuant to an effective shelf registration statement.

Varian Medical Systems, Inc. (NYSE:VAR) shares fell 4.15 percent to $71.80 in post-market trading. The company reported the first quarter net income of $95.3 million or $0.86 per share, up from $90.2 million or $0.79 per share in the same period last year but missed Reuters’ estimate of a net profit of $0.87 per share.

Vipshop Holdings Ltd. (NYSE:VIPS) shares fell 4.03 percent to $20.00 in post-market trading. The company stock surged more than 4.5 percent in regular trading.

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