Oil Reserves

So I have been doing some catch-up reading on some older The Economist magazines. Came across something I thought was interesting. This is from the June 13 - 19, 2009 issue, page 101:

Although the price of oil peaked at $147 a barrel in 2008, the world's proven oil reserves - thoses that are known and recoverable with existing technolog - fell only slightly, to 1,258 billion barrels, according to BP, a British oil company. That is 18% higher than in 1998. OPEC tightened its grip slightly in 2008, and commands slightly more than three-quarters of proven reserves. Saudi Arabia and Iran together account for almost one-third of the total. Venezuela, with nealy 8%, has the largest share of any non-Middle Eastern country. BP reckons that if the world continues to produce oil at the same rate as lst year, global supplies will last another 42 years, even if no more oil reserves are found.

I find it amazing how oil reserves in the past 10 years have actually GROWN by 18%, but the price of oil (and as of today, its spot price is $82.66/barrel) has grown by over 400%!