oil reserves bigger than reported

Current oil reserves are estimated to be 200 trillion liters. According to a article in petroleum review this value relates to oil which can be produced with a probability of 90% (proven reserves).
These figures are good for doing calculations for economical reporting and planning, as a low estimate, thing about which you can be reasonably confident. However for realistic scenario's for modelling the future, a 50% probability (proven + probable reservers) is more accurate.
Applying a 50% chance reserves are 2-3 times larger than the commonly used figures.

Let's hope this is not true, the real challenge is not oil reserves, but CO2 production.