The world’s largest oil and gas groups shed more than a billion barrels of reserves in 2014, the sharpest decline in at least six years, according to figures that show their exploration record has worsened as big discoveries dwindle.
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The world’s largest oil and gas groups shed more than a billion barrels of reserves in 2014, the sharpest decline in at least six years, according to figures that show their exploration record has worsened as big discoveries dwindle.