Oil and gas price decks: strip, flat, escalated, and SEC cases

What a price deck is

A price deck is the set of commodity price assumptions used to value oil and gas production over time. It usually contains benchmark prices for crude oil, natural gas, and natural gas liquids by year or month, the differentials that convert those benchmarks into realized prices at a specific location and quality, and sometimes cost escalation. The same production forecast produces very different values under different decks, which is why a price deck is a governed input, not a spreadsheet detail.

Operators such as EOG Resources and Devon Energy sell production across several U.S. basins, and the regional differences between where oil and gas is produced and where benchmarks are priced are material to their realized revenue. A useful deck therefore separates the benchmark from the differential and records where each number came from.

Strip, flat, escalated, and SEC cases

A strip deck uses forward prices from futures markets for the years where those markets are liquid, then holds or extrapolates prices beyond that horizon. It reflects what the market would pay today for future delivery and is common in acquisition analysis and hedging. A flat deck holds a single price constant for every year, which makes scenario comparisons simple and is often used for screening or sensitivity tables. An escalated deck starts from a base price and grows it by a fixed rate, and lenders, planners, and consultants each publish their own versions.

SEC reserves reporting uses a defined case. Under Regulation S-X Rule 4-10, existing economic conditions use the average price during the 12-month period before the end of the reporting period, calculated as an unweighted arithmetic average of the first-day-of-the-month price for each month, unless prices are defined by contract, and excluding escalations based on future conditions. Because the rule fixes the method, reported proved reserves can differ from the reserves an operator uses internally for planning under a strip or corporate deck. Both are legitimate; they answer different questions and must be labelled.

Most organizations maintain several cases at once. A corporate planning deck sets budget and capital allocation, a lender deck is defined by a bank's own price assumptions for borrowing-base redeterminations, an acquisition team may run a strip case alongside a downside case, and the reserves group prepares the SEC case for year-end reporting. Problems arise when these cases are not clearly named and a number calculated under one is quoted as if it came from another. A short register listing each active deck, its purpose, effective date, owner, and approver prevents most of that confusion and gives auditors a clear trail.

Differentials and the data boundary

Benchmark prices such as WTI, Brent, and Henry Hub rarely equal what a producer receives. Location differentials reflect transportation and regional supply, quality differentials reflect gravity, sulfur, and gas composition, and contract terms add deductions or premiums. NGL prices are often modeled as a percentage of crude or by component. Each adjustment should be a separate, dated assumption rather than folded into the benchmark, so that a reviewer can see whether a valuation change came from the market or from a changed differential.

Historical prices come from public and licensed sources. The U.S. Energy Information Administration publishes spot price history and short-term outlooks, and market-data providers supply benchmark series through feeds and APIs. Oil Price API, the publisher of BTU Graph, is one source of structured benchmark prices at this boundary. Whatever the source, store observations with timestamps, units, and currency, and keep the transformation from raw series to deck reproducible.

Governing the deck inside economics software

Reserves and economics systems such as ComboCurve, PHDwin, ARIES, and Enverus PRISM all accept price decks, and each handles scenarios and versioning differently. Test how a deck is versioned, who can approve a change, whether a prior valuation can be reproduced exactly with the deck that was used at the time, and how a deck update propagates across projects. A common failure is a deck copied into a case and edited locally, after which nobody can say which assumptions produced the reported number.

Name every case by purpose and date, such as an SEC year-end case, a strip case as of a stated date, or a board planning case, and attach the approver. Keep the deck outside the economic model as its own governed object, then import it into each system. The workflow page on building and governing energy price decks describes the control points in more detail.

Review cadence belongs in the same register. Strip decks age quickly because futures prices move every trading day, so a strip case should always carry the market date it was taken from. Corporate and lender decks are usually revised on a fixed schedule, and the SEC case changes once per reporting period. Recording the next scheduled review alongside each deck keeps stale assumptions from drifting into new valuations.

This guide is editorial research, not investment, accounting, or reserves-reporting advice. Companies and products are listed alphabetically from public evidence, and inclusion does not imply a commercial relationship. Confirm reporting requirements with qualified reserves evaluators and auditors.