Historical Ledger — Oil Lease Months — what it is, in short

What this is:

The 06 LDOLDATA segment of S.LDF900OL on its own: 29,542,093 rows, one per oil lease per reporting cycle, from January 1993 to June 2024. This is the table the Historical Ledger exists for, and it is published separately because a download is of one table and the root's 158,566 balance rows are not what anyone comes here for.

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 21 columns and about 29.5M rows.

The columns you will most likely want:

district RRC district as an INTERNAL district number, 01 to 14 -- not the designation the industry prints.
lease_no The RRC oil lease number as a whole number, so PDQ's '02092' is 2092 here.
cycle_yyyymm The reporting cycle this row belongs to, as a whole number: 202406 is June 2024.
operator_no The six-digit P-5 operator number for THIS cycle, which is what makes the file a history rather than a snapshot: a lease that changed hands in 2007 has one number before and another after.
field_no The five-digit RRC field number for this cycle, as a whole number.
field_reservoir_no The three-digit reservoir number under the field, the low end of RRC's eight-digit field key.

…and 15 more, all documented on the full page.

What we add:

Chart a lease's allowable against its production for thirty-one years; find the months a lease produced beyond its allowable and the months it worked the overage off; total oil by district and year for the whole state; or take one year -- about a million rows -- and join it to the P-5 directory to see who was operating what in 1997.

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:

FILTER ON THE CYCLE. The table is 29.5M rows partitioned by year, and a cycle range is the only filter that lets Postgres skip whole years of it. A district or an operator on their own still read every partition.

The full page lists every trap in this dataset.

Get it:

People who want this usually want:

Historical Ledger — Statewide Oil Every Texas oil lease's month back to January 1993 — allowable, production, movable balance and dispositions. 60.4 million rows.
P-5 Organization (ASCII) Every organization with an RRC operator number: name, status, type and address.
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 The gas proration schedule: every gas field in Texas and how its allowable is set.
Gas Ledger — Field Months Fourteen months of allocation factors and limited-allowable codes for every gas field.