They don't offer proof because they have none to offer. The gas and oil industry is one of the most highly regulated and closely watched industries in the world. Catching them in wrong doing would be the golden ticket for any politician, they could ride it straight to the White House.
But all that has ever been found for decades has been some petty penny ante local stuff.
No these guys are too stubborn to admit they're wrong. They hate big oil and any corportation that makes a profit, except theirs of course. Your chart is pretty clear and so has to dismiss you as an evil big oil person to ruin your credibility. Oldest trick in the book.
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