See the comment below explaining this graph and this link for further explanation (again, "anonymous" has bailed me out and taught me a lot, thank you): http://www.economist.com/blogs/dailychart/2011/06/oil-production-and-consumption. To explain the graph below, BP writes:
Update: The authors of the BP report have asked us to highlight that a large part of the difference between consumption and production, in the charts above, is accounted for by such things as biofuels, oil made from coal and other non-conventional sources, which are not included in their production figures.
