The same engine behind the Powder River Basin study, running here instead of on our machines. It fits per producing day, on the logarithm of rate, switches to a terminal decline before estimating recovery, and refuses to give you a number when the fit does not deserve one.
One row per month. Two columns is enough, volume and producing days, and a date column is accepted and ignored. Commas, tabs or spaces. Header row optional.
Rate per producing day. If you give it producing days, it divides by them. A well down for eleven days did not decline, it was off, and a fitter that cannot tell the difference forecasts your downtime forward as reservoir behaviour.
The flowback month dropped. The first partial month is choked and cleaning up. It is not on the trend that governs everything after it.
Fitted on the logarithm of rate. Production spans two orders of magnitude across a well's life. A fit on raw rate is dominated by the first six months and effectively ignores the tail, which is where the reserve lives.
A terminal switch before any recovery number. A hyperbolic with an exponent near or above one barely converges when integrated forever, and exponents that high are ordinary early in life. Without the switch a well fitted at 1.4 books sixty percent more oil than it will deliver.
It refuses. If the exponent lands on its bound, the search hit a wall rather than found an answer, and you get told that instead of a number. Most fitters report the number.
This fits one well to one curve. It does not know your costs, your working interest, your downtime causes or whether the well is under injection, and a decline curve cannot describe a well under injection at all. On the Powder River Basin study it refused 174 of 1,368 wells for exactly that kind of reason.
The engine here is the same code as the study, checked line for line against it: both implementations are run over the same cases and must agree to within one part in a million before either ships.
See what it found across 1,459 wells, or have us run it properly on your asset.
The Asset Health Check is the cheapest possible way to find out whether we are worth the larger engagement. Two weeks, fixed fee, and a written answer either way.