A means of predicting future oil well or gas well production based on the Mathematical model predicting the fluid production from a reservoir based on the past production/injection history.
It can be applied to any fluid production: water, oil gas or total production.
It does not involve the knowledge of formation pressure or bottom-hole pressure and is solely based on production/injection history data.
This comes as advantage in quick estimation of production perspectives and as disadvantage in accurate long-terms predictions.
There are many popular decline metrics, including the most popular:
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