NEW YORK (MarketWatch) -- Energy stocks traded flat-to-lower on Tuesday after losing in the previous session. The NYSE Arca Oil Index (XOI 1,072, -1.91, -0.18%) fell 0.1% to 1,072. The NYSE Arca Natural Gas Index (XNG 534.09, +0.53, +0.10%) traded flat at 534. The Philadelphia Oil Service Index edged down to 204.
