According to the latest estimates (2008), the Kingdom's recoverable reserves now stand at 267 billion barrels. (An increase in recoverable reserves, despite the daily extraction of millions of barrels of oil, is made possible by the discovery of new oil fields and improved technology in exploiting existing field.)
Current estimates mean that Saudi Arabia holds more than 21% of the world's proven oil reserves. (NB: Proved reserves of oil – Generally taken to be those quantities that geological and engineering information indicates with reasonable certainty can be recovered in the future from known reservoirs under existing economic and operating conditions.BP)
As techniques for extraction improve and new reserves are found, it is estimated that the oil reserves of the Kingdom of Saudi Arabia will last for some 90 years.