In 2013, Exxon’s market capitalization was $415 billion, and it was the most valuable firm in the world. Today, it’s worth $180 billion. In 2008, energy comprised 13.3% of the S&P 500, today, it’s 2.5%. Recently, the Dow Jones Industrial Average bid adieu to Exxon, the longest tenured firm in the index dating back to its inclusion in 1928 as Standard Oil of NJ. The Green Revolution has begun.