By Steve Gelsi
NEW YORK (MarketWatch) -- Energy stocks traded flat on Wednesday ahead of key weekly inventory data. The NYSE Arca Oil Index (XOI 1,106, -1.58, -0.14%) fell fractionally to 1,107. The NYSE Arca Natural Gas Index (XNG 561.97, -1.93, -0.34%) dipped 0.3% to 562. The Philadelphia Oil Service Index (OSX 206.91, +0.26, +0.13%) rose 0.1% to 207.
