Gas Ledger — Field Months — what it is, in short

What this is:

The FLD-MONTH group of the GSA020K field record, normalised: 589,862 rows, fourteen months for each of the 42,133 gas fields. It carries the per-well, acreage and 'other' factors of the field's allocation formula for that month, and the special limited-allowable code its wells will carry.

How it is laid out:

The Railroad Commission publishes this as EBCDIC (IBM cp037). IBM mainframe encoding (cp037). Opening it as text gives you nonsense; it has to be transcoded first. We decode it into a table you can open anywhere. It has 16 columns and about 589.9K rows.

The columns you will most likely want:

district RRC district of the field this month belongs to, in the ledger's spelling.
field_no The eight-digit field number this month belongs to.
month_ordinal Which of the fourteen month slots in the field record this row came from, 1 to 14, oldest first.
cycle_yyyymm The schedule month this row is for, CCYYMM.
change 1 when the field number changed this month. Zero in every row of the August 2026 tape.
per_well_code The per-well allocation factor code for fields with per-well in the formula; the codes are in the manual's Appendix B.

…and 10 more, all documented on the full page.

What we add:

Follow a prorated gas field's allocation factors through the cycle, and find the months a field's wells were put on a special limited allowable.

Decoded out of the Commission's original format into something Excel opens.
Filterable before you download, so you can take one county instead of the whole state.
The Commission's single-letter codes translated into words.

Worth knowing before use:

Prorated gas fields are rare, and it shows: per_well is non-zero on 51 of 589,862 rows and the acreage factor on 1,692. Most gas fields are exempt or one-well fields whose allowable needs no formula.

The full page lists every trap in this dataset.

Get it:

People who want this usually want:

Gas Ledger The gas proration schedule: every gas field in Texas and how its allowable is set.
PDQ Lease Production by Cycle Monthly oil, gas, condensate and casinghead gas production for every Texas lease since 1993.
Production Data Query Dump The whole PDQ archive: sixteen delimited tables of Texas production from 1993 to today.
Gas Ledger — Well Months Fourteen months of gas allowable against reported production, well by well.
Gas Ledger — Wells Every gas well on the proration schedule, with its gatherers, pressures and balances.
Historical Ledger — Gas Well Months 42.9 million gas well-months, 1993 to 2024: allowable, word allowable, production, overage and the well's type that month.