Reserves-to-production ratio

The reserves-to-production ratio (RPR or R/P) is the remaining amount of a non-renewable resource, expressed in time.

The production portion (denominator) of the ratio is the amount of resource produced in one year at the current rate.

However, reserve quantities can only be estimated to varying degrees of accuracy, depending on the availability of information and on the methods used to evaluate them.

[2] The reserves-to-production ratio is the most widely quoted of the key indicators used in the oil and gas industry.

The magnitude of the RPR is inversely related to the annual rate of production, which may depend on geological features.

For example, a highly fractured oil reserve with water drive may have a RPR as low as 6 years.

Non-constant values for both the numerator and denominator of the ratio implies it may either overestimate or underestimate the remaining life of the resource.

Reserve-to-production ratios may be calculated for individual countries or globally for specific resources.