Would someone explain why 10% pre-tax values (of future net revenue) are used in PV discussions? Is 10% just a method that was arbitrarily chosen to use as standard reporting throughout industry? There must be some logic to it.

"The GLJ 2008 Year-End Report estimated Connacher's 1P bitumen Reserves would generate $3.5 billion of future net revenue with a 10 percent pre-tax present value of $888 million, after deduction of future capital requirements of $2.2 billion and well abandonment costs of $32 million."