Oil: What’s Russia Really Sitting On?

In its annual statistical survey of world energy, BP PLC (BP ) has recently revised its estimates of Russia’s total proven oil reserves to 69.1 billion barrels, 6% of the world’s total, up from 45 billion bbl. in 2001.
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This increasing recoverability, and not dramatic new discoveries of oil, explains why Russia’s proven reserves keep shooting up.

BusinessWeek