As Exxon Mobil is removed from the Dow, is this the end for Big Oil?

It's not the first time that there's only been one oil and gas company in the Dow

From Monday there will be just one oil company in the Dow Jones Industrial Average — Chevron Corp. The removal of Exxon Mobil Corp. from the index after an uninterrupted presence since 1928 shouldn’t come as a surprise. It’s not the end of Big Oil, but it may signal the start of the beginning of the end.

It may seem odd to remove one of only two oil companies in the index at a time when the shale boom has transformed America's role in the global market. After all, the U.S. now produces more oil and more natural gas than any