All companies featured: Occidental Petroleum (NYSE:OXY), Dow Chemical Corporation (NYSE:DOW), Exxon Mobil Corporation (NYSE:XOM), Chevron Corporation (NYSE:CVX), Phillips 66 (NYSE:PSX), Enterprise Products Partners L.P. (NYSE:EPD), Westlake Chemical Corporation (NYSE:WLK), Royal Dutch Shell plc (NYSE:RDS.A), Pembina Pipeline Corporation (NYSE: PBA), CF Industries Holdings Incorporated (NYSE:CF)