Get the data

Free. You will be asked to confirm an email address before the files are built — that is the only gate, and it is there so we can tell you when a large export is ready.

Preview the first 100 rows

What this is

OLA013K, the oil master tape -- the schedule the Railroad Commission runs the oil business on. Eleven district volumes of 1200-byte EBCDIC records, decoded here into eight tables: a record for every oil FIELD, the LEASES in it, the MULTI-WELL groups on a lease and the individual WELLS, each with the months the tape carries inside the record.

This dataset is the field records: 33,939 of them, one per field and district, with the field's discovery date and depth, its allocation formula and yardstick, its gas-oil ratio and top allowable, the spacing its wells are drilled on, and its cumulative oil production. The fourteen months of allocation factors that hang off each field are Oil Ledger Field Months; the leases, groups and wells are datasets of their own and are listed in the record layout below.

RRC publishes the eleven volumes as separate rows on its downloads page. They share one record layout and one MFT folder, so EZRRC catalogues them as one dataset and loads all eleven into the same tables.

What you can do with it

Read the rules a field is prorated under -- the allocation formula and its weights, the yardstick, the acres and footages a proration unit must have -- and put a lease's or a well's allowable in the context of the field that set it. Cumulative production makes it a size ranking of every oil field in Texas.

Gotchas

The district is spelled the tape's way: 06E, 07B, 07C and 08A, with the leading zero. The W-10, the G-10 and PDQ write 6E, 7B, 7C and 8A. A join on the column as it stands silently drops those four districts -- 24% of the ledger's wells -- so strip the leading zero first. The district code set on this page lists both spellings.

operator_no and lease_no are zeros on every field record. The tape repeats one key layout across all four record types and a field has neither.

Several columns the 1980s manual documents are dead: remarks_1, remarks_2, annual_a, annual_b and permanent_field_no are blank in every row (RRC moved field remarks to the field information file after the December 1988 tape), and ooip, net_gor_code and alloc_pct_3 are zero throughout. The column descriptions say which.

oil_gravity keeps the tape's implied decimal: 380 is 38.0 API. It is the one V-picture field the loader deliberately did not scale, so the stored value still matches the pristine file byte for byte.

The key is district plus field number because the tape is eleven district volumes and every record repeats the district -- not because it is needed. All 33,939 field numbers are distinct, none is carried in two districts, and the PDQ field directory names the same district for every one, so join to the directory on field_no alone and skip the 06E-to-6E translation.

Record layout

263 columns. Byte positions are 1-based and come from the RRC record layout, so you can check our decoding against the original file yourself.

`oil_ledger_field` 53 columns

This is the table you get when you download or query Oil Ledger.

Record layout for `oil_ledger_field` — 53 columns, with byte positions
#	Column	Type	Bytes	RRC name	Meaning	Lookup
1	`district` key join	text	2-4	`DIST`	RRC district the field is in, as the ledger tape writes it: 01-06, 06E, 07B, 07C, 08, 08A, 09, 10 -- the lettered four carry a leading zero the W-10, the G-10 and PDQ do not use. In the key because the record carries it, not because it is needed: field numbers are unique on their own in all 33,939 rows. e.g. 01	RRC district (proration ledger spelling)
2	`field_no` key join	integer	5-12	`FIELD`	The eight-digit RRC field number: five digits identifying the field and three more for the reservoir. Unique on its own in this table (33,939 numbers in 33,939 rows), but key it with the district. e.g. 256500	—
3	`operator_no`	integer	13-18	`OPR`	Zeros on every field record -- the tape repeats the full key layout on all four record types and a field has no operator. Verified zero in all 33,939 rows.	—
4	`lease_no`	integer	19-23	`LEASE`	Zeros on every field record, for the same reason as operator_no: the key layout is shared with the lease, multi-well and well records.	—
5	`offshore`	smallint	26	`OFFSHORE`	Where the field's discovery well sits: 0 land, 1 state bays and estuaries, 2 state offshore from islands, 3 federal, 4-9 the combinations. Federal codes are no longer maintained -- RRC stopped requiring federal offshore production reports in 1980.	—
6	`field_name`	text	27-58	`F-NAME`	The field name as RRC designated it, usually an operator's word plus the formation and its depth: 'A.W.P. (OLMOS)'. 'WILDCAT' is a real value and covers wells that are not in a designated field. e.g. A.W.P. (OLMOS)	—
7	`county_code_1`	smallint	59-61	`COUNTY(1)`	First of up to six county codes the field lies in, three digits. Onshore counties are the odd numbers 1-507; the even ones are offshore areas.	—
8	`county_code_2`	smallint	62-64	`COUNTY(2)`	Second county the field lies in, or 0. Zeros fill from here on.	—
9	`county_code_3`	smallint	65-67	`COUNTY(3)`	Third county the field lies in, or 0.	—
10	`county_code_4`	smallint	68-70	`COUNTY(4)`	Fourth county the field lies in, or 0.	—
11	`county_code_5`	smallint	71-73	`COUNTY(5)`	Fifth county the field lies in, or 0.	—
12	`county_code_6`	smallint	74-76	`COUNTY(6)`	Sixth county the field lies in, or 0.	—
13	`disc_date`	date	77-84	`DISC-DATE`	Date the field's first well was completed, as a date. Null in 2,083 of 33,939 rows where the tape gave a year but zeros for the month or the day -- read disc_date_raw for those. Ranges 1896 to 2026. e.g. 1981-12-20	—
14	`disc_date_raw`	integer	77-84	`DISC-DATE`	The discovery date exactly as the tape carried it, CCYYMMDD as an integer. Kept because a month or day of 00 is meaningful here: it means the operator knew the year and not the rest.	—
15	`field_depth`	integer measured in ft	85-89	`F-DEPTH`	Depth in feet of the deepest perforation in the field's discovery well. Zero where RRC never recorded one. e.g. 9800	—
16	`oil_gravity`	smallint measured in API	90-92	`O-GRAV`	API gravity of the oil in the discovery well, as the tape's three digits with the tenth NOT separated: 380 is 38.0 API. The layout is PIC 999 with an implied decimal the loader deliberately left in place, because dividing would have changed the stored value away from the pristine file for a field nobody filters on. e.g. 380	—
17	`field_type`	smallint	93	`F-TYPE`	How the field is classified for allowable purposes: 0 regular (33,298 rows), 1 new pooled exempt, 2 reservoir MER, 3 no longer exists (520), 4 salt dome (97).	—
18	`mult_res`	smallint	94	`MULT-RES`	Whether the field is part of a multiple-reservoir structure. The manual marks this item as no longer used.	—
19	`lease_prod_basis`	smallint	95	`F-LPB`	Whether leases in this field may produce on a lease basis rather than well by well: 1 allowed, 0 not. The manual warns this item may not be updated correctly.	—
20	`exempt`	smallint	96	`F-XMT`	Whether the field is exempt from the statewide production factor set at the monthly proration hearing: 1 exempt, 0 subject to it.	—
21	`print_as_is`	smallint	97	`PRT-AS-IS`	Whether the field's allowable is calculated by computer (0) or set by hand and printed as it stands (1).	—
22	`yard`	smallint	98	`YARD`	Which yardstick schedule prorates the field's allowable by well depth and unit size: 0 none (15,865 rows), 1 the 1947 yardstick (999), 2 the 1965 yardstick (17,075).	—
23	`test_codes`	text	99-110	`T-CODES`	Twelve one-digit codes, one per month of the year, saying what W-10 testing the field owes in that month: 0 no test, 1 annual test, 2 the commingle test that follows six months after. A field testing in January and commingling in July reads '100000200000'. e.g. 000100000200	—
24	`alloc_pct_1`	numeric	111-112	`PERCNT(1)`	Weight of the first term of the field's allocation formula, as a fraction. The tape writes two digits with the point implied, and 99 means 100% -- so the maximum value here is 0.99, not 1.00. e.g. 0.99	—
25	`alloc_code_1`	smallint	113-114	`CODEF(1)`	Which allocation factor the first term weights -- per well, acres, acre-feet and so on. The codes are in the manual's Appendix C, which is not part of the record layout; eight distinct values are in use.	—
26	`alloc_pct_2`	numeric	115-116	`PERCNT(2)`	Weight of the second term of the allocation formula, 0.00 when unused.	—
27	`alloc_code_2`	smallint	117-118	`CODEF(2)`	Allocation factor of the second term, 0 when the formula has one part.	—
28	`alloc_pct_3`	numeric	119-120	`PERCNT(3)`	Weight of the third term of the allocation formula. Zero in every row of the August 2026 tape: no field currently uses a three-part formula.	—
29	`alloc_code_3`	smallint	121-122	`CODEF(3)`	Allocation factor of the third term, 0 when the formula has fewer parts.	—
30	`res_mer_amt`	integer measured in bbl/d	123-128	`RES-AMT`	The reservoir maximum efficiency rate: the daily field allowable determined to be the most efficient rate the reservoir can be produced at, prorated among its wells. Barrels per day.	—
31	`gor_code`	smallint	129	`F-GOR-CODE`	How the field's casinghead gas limit is set: 0 a gas-oil ratio (33,908 rows), 1 a flat gas limit, 2 a limit taken from the top well's limit. gor_amt holds the number.	—
32	`gor_amt`	integer measured in cf/bbl	130-134	`F-GOR-AMT`	The field gas-oil ratio in cubic feet of gas per barrel of oil, or the gas limit when gor_code says so. 2000 is the usual statewide figure and by far the commonest value here. e.g. 2000	—
33	`top_allow_code`	smallint	135	`F-TOP-CODE`	Whether the field has a regular top allowable from the yardstick (0) or a per-well maximum efficiency rate set at hearing (1, 2,879 rows).	—
34	`top_allow_amt`	smallint measured in bbl/d	136-139	`F-TOP-AMT`	The field's top daily oil allowable per well, in barrels.	—
35	`net_gor_code`	smallint	140	`F-NET-CODE`	Basis of the field's net gas-oil ratio, which lets a well produce extra gas it diverts to legal use: 0 none, 1 a ratio, 2 a limited volume, 4 unlimited, 5 based on acreage. Zero in every row of the August 2026 tape.	—
36	`net_gor_amt`	integer measured in cf/bbl	141-145	`F-NET-AMT`	The net gas-oil ratio or volume, in the unit net_gor_code names.	—
37	`unit_net`	smallint measured in acres	146-148	`UNET`	Acres that must be assigned to each proration unit -- the minimum acreage one well may be drilled on. Statewide Rule 37 is 40 acres; a field rule may raise it.	—
38	`tol_code`	smallint	149	`F-TOL-CODE`	How acreage left over after the field's proration units are laid out is allocated: 0 to the last well drilled, 1 divided among the wells on the lease.	—
39	`tol_amt`	smallint measured in acres	150-152	`F-TOL-AMT`	The tolerance acreage allotted under tol_code, in acres.	—
40	`spacing_lease_line`	smallint measured in ft	153-156	`SPAC1`	Minimum distance in feet a well must be from the nearest lease line. Statewide Rule 37 is 467 feet; field rules routinely differ.	—
41	`spacing_well`	smallint measured in ft	157-160	`SPAC2`	Minimum distance in feet between wells. The statewide rule is 1,200 feet.	—
42	`diagonal`	smallint measured in ft	161-164	`DIAG`	The diagonal of the proration unit in feet, corner to corner -- the third of the three spacing numbers a field rule sets.	—
43	`cum_prod`	bigint measured in bbl	165-171	`CUM-PROD`	Cumulative oil production of the field, in barrels, before the months carried on this tape. Packed decimal on the tape; the largest value in the August 2026 set is 5,470,158,922 barrels. e.g. 50259250	—
44	`casing`	text	172-192	`CASING`	Free-text casing requirement the Commission has set for the field, as it prints on the proration schedule. Filled in 5,152 of 33,939 rows.	—
45	`col_head`	text	193	`COL-HEAD`	Which set of column headings the field prints under on the proration schedule. A single letter; the codes are in the manual's Appendix B.	—
46	`allocation_code`	text	194	`ALO-CODE`	Which allocation formula the field uses, as one letter. The formulas themselves are in the manual's Appendix C.	—
47	`remarks_1`	text	195-260	`F-RMK1`	Field remarks that printed on the proration schedule before the December 1988 tape. Blank in every row since, and blank in all 33,939 rows here -- RRC moved field remarks to the field information file.	—
48	`remarks_2`	text	261-326	`F-RMK2`	The second line of the retired field remarks. Blank in every row.	—
49	`permanent_field_no`	text	327-331	`PERM-NO`	RRC's permanent field number, an item the manual records as no longer used. Blank in every row of the current tape.	—
50	`sp_fhc`	smallint	332	`SP-FHC`	A one-byte item the manual records as no longer used. Zero throughout.	—
51	`annual_a`	text	333-422	`AN-A`	Proration analyst's remarks for the annual field report. Blank since the December 1988 tape, and blank in every row here.	—
52	`annual_b`	text	423-457	`AN-B`	The continuation of annual_a. Blank in every row.	—
53	`ooip`	integer measured in bbl	458-465	`F-OOIP`	Original oil in place for the field, in barrels, where it forms part of the allocation formula. Zero in every row of the August 2026 tape.	—

`oil_ledger_field_month` 13 columns

Documented here because RRC ships it in the same file. It is not in a download of this dataset — it is published separately as Oil Ledger — Field Months.

Record layout for `oil_ledger_field_month` — 13 columns, with byte positions
#	Column	Type	Bytes	RRC name	Meaning	Lookup
1	`district` key join	text	2-4	`DIST`	RRC district of the field this month belongs to, in the ledger's spelling. e.g. 01	RRC district (proration ledger spelling)
2	`field_no` key join	integer	5-12	`FIELD`	The eight-digit field number this month belongs to. e.g. 256500	—
3	`month_ordinal` key	smallint	—	—	Which of the fourteen month slots in the field record this row came from, 1 to 14, oldest first. The tape rolls: every cycle the oldest slot is dropped and a new one added at the end, so ordinal 1 means 'oldest month on this tape' and nothing more. Read cycle_yyyymm for the month it actually is. e.g. 14	—
4	`cycle_yyyymm`	integer	501-506	`FM-DATE`	The schedule month this row is for, as CCYYMM -- the only thing that makes month_ordinal mean anything. The August 2026 tape runs 202506 to 202607, and every one of the 33,939 fields carries all fourteen. e.g. 202607	—
5	`per_well`	smallint measured in bbl/d	507-508	`FM-PW`	The per-well allowable amount for this month, in barrels per day, for fields whose allocation formula has a per-well term. Zero for the fields that do not (232,764 of 475,146 rows).	—
6	`acreage_factor`	numeric	509-512	`FM-AC`	The acreage factor for this month, for fields with acres in the allocation formula. Three whole numbers and four decimals on the tape; non-zero in 95,487 rows, up to 382.	—
7	`other_factor_code`	smallint	517	`FM-OTHC`	Which factor other_factor holds when the formula uses something besides per-well or acres: 1 acre feet, 2 bottom-hole pressure, 3 potential, 4 acre pounds, 5 pressure, 6 acre foot pounds, 7 acres. Zero in 473,914 of 475,146 rows.	—
8	`month_exempt_code`	smallint	518	`FM-CHG`	Whether the field was exempt from the statewide production factor this month: 1 exempt (8,078 rows), 0 not.	—
9	`prod_factor`	numeric	519-521	`FM-PROD-FACT`	The statewide production factor set at that month's proration hearing, two whole numbers and three decimals. It has been 1.000 in 475,092 of 475,146 rows -- the factor has not curtailed Texas oil for many years. e.g. 1.000	—
10	`split_prod_factor`	numeric	522-524	`FM-SPLIT-PROD-FACT`	A second production factor for the month, where one took effect after the first of the month. Zero throughout the August 2026 tape.	—
11	`split_prod_factor_date`	smallint	525-526	`FM-SPLIT-PROD-FACT-DATE`	Day of the month the split production factor took effect. Zero throughout, matching split_prod_factor.	—
12	`change_status_code`	smallint	527	`FM-JOHN`	Six here marks an oil field that can no longer reach its maximum efficiency rate. Zero in every row of the current tape.	—
13	`other_factor`	numeric	528-535	`FM-OTH`	The amount of the factor other_factor_code names -- eight whole numbers and seven decimals on the tape. The manual prints this item at record position 526; it is actually at 528, which is the one place the OLA013K layout is wrong and was found by scanning the month stamps.	—

`oil_ledger_lease` 41 columns

Documented here because RRC ships it in the same file. It is not in a download of this dataset — it is published separately as Oil Ledger — Leases.

Record layout for `oil_ledger_lease` — 41 columns, with byte positions
#	Column	Type	Bytes	RRC name	Meaning	Lookup
1	`district` key join	text	2-4	`LEASE-REC-DIST`	RRC district the lease is in, as the ledger tape writes it: 01-06, 06E, 07B, 07C, 08, 08A, 09, 10. PDQ writes the lettered four without the leading zero. e.g. 01	RRC district (proration ledger spelling)
2	`field_no` key join	integer	5-12	`LEASE-REC-FIELD`	The eight-digit field number the lease produces from. e.g. 2001	—
3	`operator_no` key join	integer	13-18	`LEASE-REC-OPR`	P-5 organization number of the lease's current operator. Lease records are ordered by it on the tape. e.g. 893	—
4	`lease_no` key join	integer	19-23	`LEASE-REC-LEASE`	The five-digit RRC oil lease number. Unique within a district: the 98,388 leases here hold 98,388 distinct district and lease pairs even though a lease can appear under more than one field number. e.g. 19016	—
5	`offshore`	smallint	26	`LEASE-REC-OFFSHORE`	Whether the lease is on land, in state bays and estuaries, offshore or a combination. Same code list as the field record.	—
6	`lease_name`	text	27-58	`L-NAME`	Lease name as filed on Form P-4, up to 32 characters and often abbreviated. e.g. EARNESTINE	—
7	`county_code_1`	smallint	59-61	`L-CO-1`	County the lease is in, three digits. A lease may span two counties. e.g. 331	—
8	`county_code_2`	smallint	62-64	`L-CO-2`	Second county the lease lies in, or 0.	—
9	`oil_gatherer`	text	65-69	`POGATH`	Five-character code of the company that transports most of the lease's oil to the first purchaser. Set in 89,296 of 98,388 rows. The gatherer's name is in the operator directory, not here. e.g. ENTMT	—
10	`gas_gatherer`	text	70-74	`PGGATH`	Five-character code of the lease's main casinghead gas gatherer. Set in 53,817 rows.	—
11	`oil_split`	smallint	75	`OSPLIT`	1 when the lease has more than one oil gatherer, in which case oil_gatherer_2 and oil_gatherer_3 name them. 21,024 rows.	—
12	`gas_split`	smallint	76	`GSPLIT`	1 when the lease has more than one gas gatherer. The other gas gatherers are not carried on this file.	—
13	`oil_gatherer_2`	text	77-81	`OOGATH`	Second oil gatherer, where oil_split is 1.	—
14	`oil_gatherer_3`	text	82-86	`OGGATH`	Third oil gatherer, where one exists.	—
15	`prior_operator_no`	integer	87-92	`OOPR`	P-5 number of the operator who held the lease before the present one. Set in 71,296 of 98,388 rows.	—
16	`beg_oil_status`	integer measured in bbl	93-96	`BO-STATUS`	The lease's oil overproduction balance before the twelve months on this tape, in barrels. Positive means overproduced; zero means it was not.	—
17	`beg_gas_status`	integer measured in MCF	97-100	`BG-STATUS`	The lease's casinghead gas overproduction balance before the twelve months on this tape, in MCF.	—
18	`moveable_balance`	integer measured in bbl	101-104	`MOVE-BAL`	Barrels in storage on the lease that were produced within the allowable and so may be moved off it. A negative value is oil produced beyond the allowable. Accurate as of the last production month on the tape.	—
19	`present_oil_status`	integer measured in bbl	105-108	`PO-STATUS`	Oil overproduction balance in barrels at the end of the last production month on the tape. Only months whose P-1 was received are counted. Non-zero on 7,486 leases.	—
20	`present_gas_status`	integer measured in MCF	109-112	`PG-STATUS`	Casinghead gas overproduction balance in MCF at the end of the last production month reported.	—
21	`sec_rec`	smallint	113	`SEC-REC`	Nine here makes RRC's discrepancy listing print a corrected-allowable message for the lease. 12,373 rows.	—
22	`cert`	smallint	114-115	`CERT`	Day of the month the P-1 was signed, plus 40 if it was posted in the following month; 77 means a prior period and 00 clears the date. Zero in every row of the August 2026 tape.	—
23	`batch`	text	116	`BATCH`	RRC's internal batch letter for a bundle of P-1 update forms. Blank in every row of the current tape.	—
24	`lease_prod_basis`	smallint	117	`L-LPB`	1 when the lease may produce on a lease basis -- the whole lease allowable from any well on it -- rather than well by well. 1,151 rows.	—
25	`commingle_code`	smallint	118	`COMMINGLE-CD`	Status of the lease's oil commingling permit: 0 not used, 1 permit in effect (38,099 rows), 2 terminated (5,713), 4-6 the permit-number changes.	—
26	`commingle_no`	smallint	119-122	`COMMINGLE`	The commingling permit number, or one of RRC's permit codes: 8888 gas plant, 9999 multiple permits, 9898 casinghead with different royalty interests, 9696 gas metering, 9595 lease automatic custody transfer.	—
27	`lease_info`	text	123-176	`L-INFO`	Free-text note from a proration analyst that prints on the schedule. Set on 1,910 leases.	—
28	`adj_oil_status`	integer measured in bbl	177-180	`AD-BO-STATUS`	A replacement beginning oil balance, used when a well was added to or dropped from the lease inside the twelve months; the month it took effect carries change_status_code 1. Zero in every row of the August 2026 tape.	—
29	`adj_gas_status`	integer measured in MCF	181-184	`AD-BG-STATUS`	The same adjustment for the gas balance. Zero throughout the current tape.	—
30	`commingle_yyyymm`	integer	185-190	`COMMINGLE-DATE`	Month the commingling permit took effect, CCYYMM. Set on 43,457 leases.	—
31	`removal_code`	smallint	191	`L-RMCD`	Why the lease left the proration schedule: 0 it did not, 1 plugged, recompleted or plugged back (12,528 rows), 2 consolidated, unitised, subdivided or otherwise transferred (1,623).	—
32	`removal_yyyymm`	integer	192-197	`L-RMDT`	Month the lease was removed from the schedule, CCYYMM. Set on 869 leases.	—
33	`sev_code_13`	smallint	198	`SEV-CD-13`	Severance status in the month after the last one on the tape: 0 not severed, 1 severed (21,076 rows), 2 reconnected. A severance letter stops oil and gas leaving the lease until it is back in compliance.	—
34	`sev_code_14`	smallint	199	`SEV-CD-14`	Severance status two months after the last month on the tape. Same codes.	—
35	`casinghead_si_letter_yyyymm`	integer	200-205	`L-CAS-SI-LTR-DTE`	Month a casinghead shut-in letter went to the operator, CCYYMM. Set on five leases in the August 2026 tape.	—
36	`reduced_rate_yyyymm`	integer	206-211	`L-RED-RTE-DTE`	Month a reduced-rate allowable took effect after a casinghead shut-in letter, CCYYMM. Empty throughout the current tape.	—
37	`exc_test`	smallint	212	`L-EXC-TST`	The lease's exception to W-10 testing: 0 the field's regular test (94,299 rows), 1 none required, 2 no commingle test because the lease is metered (3,089), 3 survey only, 4 partial commingle, 5 and 6 lease automatic custody transfer, 7-9 a district-office month's grace.	—
38	`royalty_code`	smallint	213	`L-RLTYCD`	Whether the lease is on state land: 0 private, 1 public school land, 2 the University of Texas system, 3 another state fund.	—
39	`one_well_lease`	text	214	`L-ONE-WELL-LEASE`	'Y' on a lease with a single uncommingled well producing on a valid allowable, which exempts it from W-10 testing. Set once a year at the annual survey; 16,270 of 98,388 leases. e.g. N	—
40	`panhandle_gor_exc`	text	215	`L-PANHANDLE-GOR-EXC`	'Y' where the lease may test on a lease basis instead of well by well because its annual gas-oil ratio is 5,000 cubic feet per barrel or less. The manual describes this as applying only to eight Panhandle field numbers; the August 2026 tape carries 'Y' on 46,511 of 98,388 leases, so treat it as a lease-basis test flag rather than a Panhandle marker.	—
41	`panhandle_gor_amt`	numeric measured in MCF/bbl	216-220	`L-PANHANDLE-GOR-AMT`	The calculated annual gas-oil ratio for the lease, in thousand cubic feet per barrel to one decimal place. Anything above 5.0 has been forced to 5.1 to mark a lease that does not qualify -- so values between 5.1 and the tape's maximum of 25,079.0 are real ratios from leases that never had the flag applied.	—

`oil_ledger_lease_month` 25 columns

Documented here because RRC ships it in the same file. It is not in a download of this dataset — it is published separately as Oil Ledger — Lease Months.

Record layout for `oil_ledger_lease_month` — 25 columns, with byte positions
#	Column	Type	Bytes	RRC name	Meaning	Lookup
1	`district` key join	text	2-4	`LEASE-REC-DIST`	RRC district of the lease this month belongs to, in the ledger's spelling. e.g. 01	RRC district (proration ledger spelling)
2	`field_no` key join	integer	5-12	`LEASE-REC-FIELD`	Field number of the lease this month belongs to.	—
3	`operator_no` key join	integer	13-18	`LEASE-REC-OPR`	P-5 number of the lease operator.	—
4	`lease_no` key join	integer	19-23	`LEASE-REC-LEASE`	The five-digit oil lease number. e.g. 19016	—
5	`month_ordinal` key	smallint	—	—	Which of the twelve month slots in the lease record this row came from, 1 to 12, oldest first. The lease record carries twelve months where the field, multi-well and well records carry fourteen. The ordinal is a position on a rolling tape, not a date: use cycle_yyyymm. e.g. 12	—
6	`cycle_yyyymm`	integer	225-230	`L-MONTH-DATE`	The production month this row reports, CCYYMM. The August 2026 tape runs 202506 to 202605, and every one of the 98,388 leases carries all twelve. e.g. 202605	—
7	`severance`	smallint	231	`LM-SEV`	1 when a lease severance letter was issued this month, stopping oil and gas from leaving the lease. 236,699 of 1,180,656 rows.	—
8	`retro`	smallint	232	`LM-RETRO`	1 when a retroactive allowable change or a late production report arrived this month. 318,330 rows; the code is cleared on the next ledger.	—
9	`rec`	smallint	233	`LM-REC`	Whether the month's P-1 production report was received: 0 not received (273,495 rows), 1 received (622,202), 2 corrected allowable with a P-1 filed, 3 corrected allowable without one, 4 a corrected P-1.	—
10	`name_change`	smallint	234	`LM-CHG`	What changed this month: 1 field name, 2 operator name, 3 lease name, 5 casinghead gatherer, 6 a combination, 7 oil gatherer, 8 no allowable so remarks print, 9 lease removed then reinstated.	—
11	`oil_allow`	integer measured in bbl	235-238	`LM-ALLOW`	The lease's oil allowable for the month, in barrels. Non-zero on 702,551 of 1,180,656 rows.	—
12	`oil_prod`	integer measured in bbl	239-242	`LM-PROD`	Oil the operator reported producing from the lease this month on Form P-1, in barrels. Never negative on the current tape.	—
13	`flowing_wells`	smallint	243-245	`LM-FW`	Number of wells the operator reported as flowing on their own reservoir pressure. Three digits: a lease with more than 999 shows only the last three.	—
14	`other_wells`	smallint	246-248	`LM-OW`	Number of producing wells reported as pumping, gas lift or jetting rather than flowing. Also truncated to three digits.	—
15	`disp_amt_1`	integer measured in bbl	249-252	`LM-PL`	Barrels disposed of by the primary method, which disp_code_1 names. When a pipeline amount is reported it always goes here, whether or not it is the largest.	—
16	`disp_code_1`	smallint	253	`LM-PLC`	Primary disposition: 0 pipeline (904,479 rows), 1 trucks (275,788), 2 tank cars or barge, 3 net oil from tank cleaning, 4 circulating oil, 5 lost, 6 sedimentation, 7 other or combined, 8 skim oil, 9 scrubber oil. e.g. 0	—
17	`disp_amt_2`	integer measured in bbl	254-257	`LM-OTH`	Barrels disposed of by the secondary method. Two or more secondary methods are added together and coded 7.	—
18	`disp_code_2`	smallint	258	`LM-OTHC`	Secondary disposition, same list as disp_code_1 except that 0 means no code rather than pipeline. 8 (skim oil) is the commonest non-zero value at 96,480 rows.	—
19	`oil_in_storage`	integer measured in bbl	259-262	`LM-STO`	Barrels of oil in storage on the lease at the end of the month.	—
20	`gas_limit`	integer measured in MCF	263-267	`LM-GL`	The lease casinghead gas limit for the month, in MCF -- how much gas the lease may produce alongside its oil. Null where the tape carried all nines, which is RRC's way of writing 'no limit': 9,105 of 1,180,656 rows.	—
21	`gas_prod`	integer measured in MCF	268-272	`LM-GPROD`	Casinghead gas the operator reported for the month on Form P-1, in MCF, with any gas used for gas lift already subtracted.	—
22	`gas_lift`	integer measured in MCF	273-276	`LM-GLIFT`	Gas-lift gas produced, in MCF -- gas injected down the well and produced again, subtracted from gas_prod. Zero in every row of the August 2026 tape.	—
23	`casinghead_letter`	smallint	277	`LM-CSIL`	1 when a casinghead shut-in letter went out this month. Twelve rows in the whole tape.	—
24	`change_status_code`	smallint	278	`LM-JOHN`	1 when the adjusted oil or gas balance took effect this month. Zero in every row of the current tape, matching the empty adj_* columns on the lease record.	—
25	`letter_code`	smallint	279	`LM-LTR-CODE`	RRC's internal delinquent-or-discrepant flag: 1 no P-1, 3 oil reported without gas, 4 gas without oil, 5 out of balance, 6 the well count disagrees, 7 an impossible disposition code. Zero in every row of the August 2026 tape.	—

`oil_ledger_multiwell` 25 columns

Documented here because RRC ships it in the same file. It is not in a download of this dataset — it is published separately as Oil Ledger — Multi-Well Groups.

Record layout for `oil_ledger_multiwell` — 25 columns, with byte positions
#	Column	Type	Bytes	RRC name	Meaning	Lookup
1	`district` key join	text	2-4	`MULTI-W-REC-DIST`	RRC district the multi-well group is in, in the ledger's spelling. e.g. 08	RRC district (proration ledger spelling)
2	`field_no` key join	integer	5-12	`MULTI-W-REC-FIELD`	The eight-digit field number the group produces from.	—
3	`operator_no` key join	integer	13-18	`MULTI-W-REC-OPR`	P-5 organization number of the lease operator.	—
4	`lease_no` key join	integer	19-23	`MULTI-W-REC-LEASE`	The five-digit oil lease number the group sits on.	—
5	`offshore`	smallint	26	`MULTI-W-REC-OFFSHORE`	Land, bay, offshore or a combination, on the same code list as the field record.	—
6	`m_record` key	text	27-32	`M-RECORD`	The group's identifier within the lease, one character right-justified in six bytes -- so it arrives as ' 1' or ' A' and the blanks are kept because they are in the file. A digit usually means a waterflood grouping. This is the value the detail-well tape carries as rec_no. e.g. ' 1'	—
7	`type_wells`	text	33	`TYPEW`	Status of the wells in the group as it prints on the schedule: P or blank prorated (3,197 rows), M marginal, X exempt (323), S shut-in (153), A abandoned. e.g. P	—
8	`reservoir`	text	34-38	`RESER`	Reservoir information kept for some old leases; for Yates-field groups the same bytes hold unit_no and unit_value instead. Blank in every row of the August 2026 tape.	—
9	`unit_no`	text	34	`UNIT-NO-I`	Unit letter of a Yates-field multi-well group, redefining the first byte of reservoir. Blank throughout the current tape.	—
10	`unit_value`	numeric	35-38	`UNIT-VALUE`	The Yates unit's productive potential relative to the other units in the field, one whole number and three decimals, used to split the field allowable. Zero throughout the current tape.	—
11	`county_code_1`	smallint	39-41	`M-CO-1`	County the multi-well group is in, three digits.	—
12	`county_code_2`	smallint	42-44	`M-CO-2`	Second county the group spans, or 0.	—
13	`test_eff`	text	45	`M-TST-EFF`	Month the group's W-10 becomes effective: 1-9 for January to September, A, B, C for October to December, 0 none. Blank in every row of the August 2026 tape -- the well records carry it instead.	—
14	`pointer_first`	integer	46-51	`M-PNTR-1ST`	RRC's internal key to the group's first record in the detail-well file. Set on all 3,713 groups. It is a mainframe pointer, not a join key: use district, field, operator, lease and m_record.	—
15	`capacity`	smallint	52	`CAP`	1 when the wells in the unit may produce at capacity, exempt from the production factor -- the allowable a waterflood project gets after a response is proved. 522 of 3,713 groups. e.g. 0	—
16	`prod_wells`	smallint	53-55	`M-PROD`	Number of producing wells in the group. Up to 659 in the August 2026 tape.	—
17	`inj_wells`	smallint	56-58	`M-INJ`	Number of injection wells in the group -- the water or gas injectors that make it a secondary recovery project. Non-zero on 1,398 groups.	—
18	`shut_in_wells`	smallint	59-61	`M-SHUT`	Number of shut-in wells in the group.	—
19	`marg_wells`	smallint	62-64	`M-MARG`	Number of marginal wells in the group: artificial-lift wells that produce to capacity under the marginal well law, exempt from the production factor.	—
20	`depth_code`	smallint	65	`M-DEPTH`	Depth band of the wells in the group: 1 to 2,000 feet, 2 to 4,000, 3 to 6,000, 4 to 8,000, 5 deeper, 0 not used.	—
21	`pointer_last`	integer	66-71	`M-PNTR-LST`	RRC's internal key to the group's last record in the detail-well file.	—
22	`exc_test`	smallint	72	`M-EXC-TEST`	The group's exception to the lease's testing: 0 regular test required (3,617 rows), 1 none, 2 no commingle test, 3 no survey, 4 commingle test required for the commingled wells of a partially commingled lease.	—
23	`water`	integer measured in bbl	79-84	`M-WATER`	Barrels of water produced with the oil, on the group's test.	—
24	`remark`	text	85-139	`M-REMARK`	Free-text remark about the group from a proration analyst, printed on the schedule. Set on 1,070 of 3,713 groups.	—
25	`pct_first_county`	numeric	140-142	`MM-PRCNT`	Share of the allowable produced from wells in county_code_1, for a group that spans counties -- used to split lease production by county on the annual report. Zero throughout the current tape.	—

`oil_ledger_multiwell_month` 28 columns

Documented here because RRC ships it in the same file. It is not in a download of this dataset — it is published separately as Oil Ledger — Multi-Well Group Months.

Record layout for `oil_ledger_multiwell_month` — 28 columns, with byte positions
#	Column	Type	Bytes	RRC name	Meaning	Lookup
1	`district` key join	text	2-4	`MULTI-W-REC-DIST`	RRC district of the multi-well group this month belongs to, in the ledger's spelling. e.g. 08	RRC district (proration ledger spelling)
2	`field_no` key join	integer	5-12	`MULTI-W-REC-FIELD`	Field number of the group.	—
3	`operator_no` key join	integer	13-18	`MULTI-W-REC-OPR`	P-5 number of the lease operator.	—
4	`lease_no` key join	integer	19-23	`MULTI-W-REC-LEASE`	The five-digit oil lease number.	—
5	`m_record` key	text	27-32	`M-RECORD`	The group's identifier within the lease, right-justified in six bytes. e.g. ' 1'	—
6	`month_ordinal` key	smallint	—	—	Which of the fourteen month slots in the multi-well record this row came from, 1 to 14, oldest first. A position on a rolling tape; cycle_yyyymm is the month itself. e.g. 14	—
7	`cycle_yyyymm`	integer	165-170	`M-MONTH-DATE`	The schedule month this row is for, CCYYMM. The August 2026 tape runs 202506 to 202607. e.g. 202607	—
8	`change`	smallint	171	`MM-CHG`	What changed this month: 1 field name, 2 operator name, 3 lease name, 4 well number, 6 a combination, 0 nothing.	—
9	`no_supp`	smallint	172	`MM-NO`	Whether the month's allowable supplement is trustworthy: 0 fine, 1 an asterisk was printed for an analyst to check, 2 it is the new month and no supplement is allowed. Zero throughout the current tape.	—
10	`oil_allow`	integer measured in bbl/d	173-176	`MM-ALLOW`	Daily oil allowable for the group from the first of the month, in barrels, until a supplement or the next month's schedule replaces it. Non-zero on 35,522 of 51,982 rows.	—
11	`acode`	text	177	`MM-ACODE`	Whether that allowable is limited and why: 0 not limited, 1 limited by test or potential (38,986 rows), 2 limited by the group's own previous production. Read together with tcode. e.g. 1	—
12	`tcode`	text	178	`MM-TCODE`	What kind of well group the allowable was assigned to: 0 prorated (40,092 rows), 3 marginal, 5 shut-in (7,409), 7 exempt from the production factor (4,077). If form_lacking is 1 the wells are shut in for a delinquent W-10. e.g. 0	—
13	`gas_allow`	integer measured in MCF/d	179-183	`MM-LIMIT`	Daily casinghead gas allowable for the group this month, in MCF. Null where the tape carried all nines, RRC's 'no limit': 6,318 of 51,982 rows.	—
14	`oil_allow_2`	integer measured in bbl/d	184-187	`MM-ALLOW2`	Daily oil allowable set by the month's first supplement, effective from date_2. Zero in every row of the August 2026 tape.	—
15	`acode_2`	text	188	`MM-ACODE2`	Limit code of the first supplemental allowable, same values as acode.	—
16	`tcode_2`	text	189	`MM-TCODE2`	Type code of the first supplemental allowable, same values as tcode.	—
17	`gas_allow_2`	integer measured in MCF/d	190-194	`MM-LIMIT2`	Daily gas allowable set by the first supplement, in MCF.	—
18	`date_2`	smallint	195-196	`MM-DATE2`	Day of the month the first supplement took effect, 1 to 31.	—
19	`oil_allow_3`	integer measured in bbl/d	197-200	`MM-ALLOW3`	Daily oil allowable set by the month's second supplement, effective from date_3. Zero in every row of the current tape.	—
20	`acode_3`	text	201	`MM-ACODE3`	Limit code of the second supplemental allowable.	—
21	`tcode_3`	text	202	`MM-TCODE3`	Type code of the second supplemental allowable.	—
22	`gas_allow_3`	integer measured in MCF/d	203-207	`MM-LIMIT3`	Daily gas allowable set by the second supplement, in MCF.	—
23	`date_3`	smallint	208-209	`MM-DATE3`	Day of the month the second supplement took effect.	—
24	`form_lacking`	smallint	210	`MM-FORM-LCK`	1 when a W-10 for this group is delinquent, which shuts the wells in. Zero in every row of the August 2026 tape.	—
25	`potential`	integer measured in bbl/d	211-214	`MM-SPACE1`	Combined potential of the wells in the group -- the most they could produce together, in barrels per day. Non-zero on 39,015 rows.	—
26	`kode_2`	smallint	215	`MM-KODE2`	An item the manual records as no longer used. Zero throughout.	—
27	`gor`	integer measured in cf/bbl	216-219	`MM-SPACE2`	Gas-oil ratio of the wells in the group, in cubic feet per barrel. Non-zero on 126 rows of 51,982.	—
28	`change_status_code`	smallint	220	`MM-JOHN`	1 when the group's allowable was changed this month.	—

`oil_ledger_well` 41 columns

Documented here because RRC ships it in the same file. It is not in a download of this dataset — it is published separately as Oil Ledger — Wells.

Record layout for `oil_ledger_well` — 41 columns, with byte positions
#	Column	Type	Bytes	RRC name	Meaning	Lookup
1	`district` key join	text	2-4	`WELL-REC-DIST`	RRC district the well is in, as the ledger tape writes it: 01-06, 06E, 07B, 07C, 08, 08A, 09, 10. 50,492 of the 207,544 wells are in the lettered four, which the W-10 and PDQ write without the leading zero. e.g. 01	RRC district (proration ledger spelling)
2	`field_no` key join	integer	5-12	`WELL-REC-FIELD`	The eight-digit field number the well produces from. e.g. 2001	—
3	`operator_no` key join	integer	13-18	`WELL-REC-OPR`	P-5 organization number of the lease operator. e.g. 893	—
4	`lease_no` key join	integer	19-23	`WELL-REC-LEASE`	The five-digit oil lease number the well is on. e.g. 19016	—
5	`offshore`	smallint	26	`WELL-REC-OFFSHORE`	Land, bay, offshore or a combination, on the field record's code list.	—
6	`well_no` key	text	27-32	`WELL-NO`	The operator's well number, six bytes and positional: the tape right-justifies it and the loader keeps the leading blanks while dropping the trailing ones, so well 1 arrives as ' 1' and 1H as ' 1H'. 174,528 of the 207,544 rows are padded. They are kept because two wells can differ only in their padding. Trim before joining to the W-10 file or to PDQ. e.g. ' 1'	—
7	`type_well`	text	33	`W-TYPE-WELL`	Status of the well as it prints on the schedule: P prorated (128,731 rows), S shut-in (41,631), E shut-in with a 14(B)(2) exception (36,400), M marginal, X exempt, A abandoned, N new pooled exempt, and also D disposal, G gas injection and W water injection. e.g. S	—
8	`unit_no`	text	34	`UNIT-NO-I`	Unit letter for a Yates-field well, redefining the first byte of the reservoir name. The August 2026 tape holds '0' on 203,909 wells, blank on 3,631 and a real 'A' on four -- read it as unused outside Yates.	—
9	`unit_value`	numeric	35-38	`UNIT-VALUE`	The Yates unit's productive potential relative to the field's other units, one whole number and three decimals. Non-zero on four wells.	—
10	`w_key`	smallint	39	`W-KEY`	Depth band of the well, or 9 for a key well whose potential represents the field: 1 to 2,000 feet, 2 to 4,000, 3 to 6,000, 4 to 8,000, 5 deeper. One key well in the whole August 2026 tape.	—
11	`county_code`	smallint	40-42	`W-COUNTY`	The three-digit county code the well is in.	—
12	`pump`	text	43	`PUMP`	How the well produces: 0 flowing (80,183 rows), 1 pumping (103,337), 2 gas lift (19,503), 3 gas lift under a 10,000:1 exception, 4 vacuum, 5 casing leak, 6 designate well, 7 receiving well, 8 water well shut down. The tape also carries 'B' on 228 wells, which OLA013K does not list. e.g. 0	—
13	`special_allow_code`	smallint	44	`W-SP-CODE`	What kind of special allowable the well has, if any: 1 subject to the production factor and fixed, 2 exempt and fixed (817 rows), 3 the field top allowable prorated, 4 the field top allowable exempt.	—
14	`special_allow_amt`	smallint measured in bbl/d	45-48	`W-SP-AMT`	The special allowable amount in barrels per day. Fields on 'Z' allocation carry their top allowable here.	—
15	`net_gor_code`	smallint	49	`W-N-CODE`	Whether the well is on the net gas-oil ratio rule and how: 1 a special ratio, 2 a special daily amount, 3 unlimited, 4 based on acreage, 0 not on the rule.	—
16	`net_gor_amt`	integer measured in cf/bbl	50-54	`W-N-AMT`	The ratio or volume allowed under the net gas-oil ratio rule.	—
17	`depth`	integer measured in ft	55-59	`W-DEPTH`	Total depth of the well in feet. Non-zero on 188,812 of 207,544 wells; the deepest in the August 2026 tape is 25,515 feet. e.g. 4280	—
18	`sand`	smallint measured in ft	60-62	`SAND`	Thickness in feet of the producing zone, used only where the allocation formula needs it. For a Yates well it holds the number of wells in the unit instead. Non-zero on 216 wells.	—
19	`frozen_potential`	integer measured in bbl/d	63-67	`FROZEN`	The well's original potential in barrels per day, which does not change with production -- used where potential is part of the field's allocation formula. It also holds the rounded working potential when the month's potential column reads 9999.9. Non-zero on 4,362 wells.	—
20	`perf`	integer measured in ft	68-72	`PERF`	Depth in feet of the lowest perforation, which is the depth the allowable is calculated from. For Yates and Hastings West wells it holds the working potential instead when the month's potential reads 9999.9.	—
21	`completion_date`	date	73-80	`W-DATE`	Date the operator reported the well complete. Null in 305 rows where the tape's eight digits do not make a date; for a Yates well these bytes hold the unit potential rather than a date, which is why completion_date_raw is kept beside it. The earliest parsed value is 1900-01-03, itself a placeholder. e.g. 2017-01-04	—
22	`completion_date_raw`	integer	73-80	`W-DATE`	The completion date exactly as the tape carried it, CCYYMMDD as an integer. Read this when completion_date is null.	—
23	`ex14b_code`	text	81	`EX-14B-CD`	The well's standing under Statewide Rule 14(B)(2), which requires an abandoned well to be plugged: 0 no exception (148,623 rows), 1 exception in effect (40,371), 4 denied, plus the newer letters the tape carries -- H an H-15 violation (6,937), P partially plugged, B the inactive side of a multiple completion, L a legal violation. e.g. 4	—
24	`sub_well`	text	82	`W-SUB-WELL`	What a shut-in well is being used for: 1 dry hole, 2 water supply, 3 observation, 4 gas storage, 5 LPG storage, 6 other service, 7 sealed, 8 field operation, 9 other injection (9,928 rows), 0 not shut in. The tape also carries 'S' on 51 wells, which the manual does not list.	—
25	`no_prod_code`	smallint	83	`W-NO-PROD-CD`	Why the allowable was cut: 1 a delinquent P-1, 2 no production (20,511 rows), 0 neither.	—
26	`delq_form`	smallint	84	`W-DELQ-FORM`	1 when the well is shut in because of a delinquent form.	—
27	`test_eff`	text	85	`W-TST-EFF`	Month the well's W-10 becomes effective: 1-9 January to September, A, B, C October to December, 0 none. The commonest value in the August 2026 tape is A, on 38,052 wells. e.g. 1	—
28	`exc_test`	smallint	86	`W-EXC-TST`	The well's exception to the testing its lease owes: 0 regular test (188,008 rows), 1 no W-10 required, 2 no commingle test, 3 no survey, 4 commingle test required on a partially commingled lease, 5 the one-well-lease exception (16,399).	—
29	`water`	smallint measured in bbl	87-90	`W-WATER`	Barrels of water produced with the oil on the well's test, usually over 24 hours.	—
30	`ex14b_yyyymm`	integer	91-96	`EX-14B-DATE`	Month the well's 14(B)(2) exception expires, CCYYMM. Set on 52,344 wells.	—
31	`remarks`	text	97-111	`W-RMKS`	Fifteen characters of schedule remarks about the well, from an analyst or generated by RRC's own programs. Set on 119,845 wells.	—
32	`bonus_code`	smallint	112	`BONUS-CD`	Whether the well gets a bonus allowable on top of its calculated one: 1 gas bonus, 2 oil bonus, 3 oil injection allowable, 0 none. Twenty-two wells in the whole August 2026 tape.	—
33	`bonus_amt`	smallint measured in bbl/d	113-115	`BONUS`	The daily bonus allowable in barrels or MCF, per bonus_code.	—
34	`max_transfer`	smallint measured in bbl/d	116-118	`FROZTSF`	The largest daily allowable transfer the well may receive on top of its own, in barrels. Non-zero on twelve wells.	—
35	`water_ratio_exc`	smallint	119	`W-WLSD`	9 when a District 6E well has an exception to the East Texas field's water-oil ratio rule. Twenty-two wells.	—
36	`test_date`	date	120-127	`W-TST-DT`	Date of the last W-10 test filed for the well. Present on 205,705 of 207,544 wells, ranging from 1973 to July 2026. e.g. 2020-06-01	—
37	`date_last_utilized_yyyymm`	integer	128-133	`W-DTE-LST-UTL`	Month a shut-in well was last used, CCYYMM. Set on 16,052 wells.	—
38	`new_wellbore_exc`	text	134	`W-NEW-WB-EXC`	'Y' when a Panhandle well qualifies as a new wellbore and may produce twice the daily gas maximum for two years from its pipeline connection. 2,724 wells.	—
39	`new_wellbore_connect_date`	date	135-142	`W-NEW-WB-CONNECT-DATE`	Date of the new wellbore's gas pipeline connection.	—
40	`ex14b2_type`	text	143	`W-14B2-TYPE-COVERAGE`	How the well's 14(B)(2) exception is covered: B a blanket bond, M a mini-bond, S a single lease, R a secondary recovery project, W a W-1X, N none. Blank in every row of the August 2026 tape.	—
41	`ex14b2_app_no`	integer	144-149	`W-14B2-APP-NO`	Application number of the 14(B)(2) coverage, RRC's key into its own exception database. Zero in every row of the current tape.	—

`oil_ledger_well_month` 37 columns

Documented here because RRC ships it in the same file. It is not in a download of this dataset — it is published separately as Oil Ledger — Well Months.

Record layout for `oil_ledger_well_month` — 37 columns, with byte positions
#	Column	Type	Bytes	RRC name	Meaning	Lookup
1	`district` key join	text	2-4	`WELL-REC-DIST`	RRC district of the well this month belongs to, in the ledger's spelling. e.g. 01	RRC district (proration ledger spelling)
2	`field_no` key join	integer	5-12	`WELL-REC-FIELD`	Field number the well produces from.	—
3	`operator_no` key join	integer	13-18	`WELL-REC-OPR`	P-5 number of the lease operator.	—
4	`lease_no` key join	integer	19-23	`WELL-REC-LEASE`	The five-digit oil lease number. e.g. 19016	—
5	`well_no` key	text	27-32	`WELL-NO`	The operator's well number, right-justified in six bytes as the tape wrote it. e.g. ' 1'	—
6	`month_ordinal` key	smallint	—	—	Which of the fourteen month slots in the well record this row came from, 1 to 14, oldest first. It is a position on a rolling tape and not a date -- every month the oldest slot is dropped and a new one added at the end. cycle_yyyymm is the month. e.g. 14	—
7	`cycle_yyyymm`	integer	179-184	`W-MONTH-DATE`	The schedule month this row is for, CCYYMM. The August 2026 tape runs 202506 to 202607, and every one of the 207,544 wells carries all fourteen. e.g. 202607	—
8	`change`	smallint	185	`WM-CHG`	What changed this month: 1 field name, 2 operator name, 3 lease name, 4 well number, 5 a combination. Zero in every row of the August 2026 tape.	—
9	`no_supp`	smallint	186	`WM-NO`	Whether the month's supplement is trustworthy: 1 it may be in error, 2 it is the new month and no supplement is allowed. Zero throughout the current tape.	—
10	`oil_allow`	integer measured in bbl/d	187-189	`WM-ALLOW`	The well's daily oil allowable from the first of the month, in barrels, before any transfer. Non-zero on 1,757,204 of 2,905,616 rows; the largest is 12,938 barrels a day.	—
11	`acode`	text	190	`WM-ACODE`	Whether that allowable is limited and why. The manual defers to its Appendix D, which is not part of the record layout; the August 2026 tape carries 0, 1, 2, 6, 7 and 8, with 1 on 1.6 million rows. e.g. 8	—
12	`tcode`	text	191	`WM-TCODE`	The status the allowable was assigned under -- prorated, marginal, shut-in, exempt. Also an Appendix D list; the tape carries 0, 2, 5, 6, 9 and B. Read it with acode: the pair is one two-digit code. e.g. 2	—
13	`gas_allow`	integer measured in MCF/d	192-195	`WM-LIMIT`	The well's daily casinghead gas allowable for the month, in MCF. Null where the tape carried all nines, RRC's 'no limit': 15,742 of 2,905,616 rows.	—
14	`oil_allow_2`	integer measured in bbl/d	196-198	`WM-ALLOW2`	Daily oil allowable set by the month's first supplement, effective from date_2 until the second supplement or the end of the month. Non-zero on 13,575 rows.	—
15	`acode_2`	text	199	`WM-ACODE2`	Limit code of the first supplemental allowable.	—
16	`tcode_2`	text	200	`WM-TCODE2`	Type code of the first supplemental allowable.	—
17	`gas_allow_2`	integer measured in MCF/d	201-204	`WM-LIMIT2`	Daily gas allowable set by the first supplement, in MCF.	—
18	`date_2`	smallint	205-206	`WM-DATE2`	Day of the month the first supplement took effect. Non-zero on 19,161 rows.	—
19	`oil_allow_3`	integer measured in bbl/d	207-209	`WM-ALLOW3`	Daily oil allowable set by the month's second supplement, from date_3.	—
20	`acode_3`	text	210	`WM-ACODE3`	Limit code of the second supplemental allowable.	—
21	`tcode_3`	text	211	`WM-TCODE3`	Type code of the second supplemental allowable.	—
22	`gas_allow_3`	integer measured in MCF/d	212-215	`WM-LIMIT3`	Daily gas allowable set by the second supplement, in MCF.	—
23	`date_3`	smallint	216-217	`WM-DATE3`	Day of the month the second supplement took effect.	—
24	`form_lacking`	smallint	218	`WM-FORM-LCK`	How many months the well's W-10 has been delinquent, 1 to 9, incrementing each month; 0 when the form was received. Non-zero on 185,461 rows.	—
25	`prorated_gas_transfer`	smallint measured in MCF/d	219-220	`WM-PGT`	Daily gas transferred to or from the well, in MCF, on top of its regular gas allowable and subject to the production factor. Needs oil_transfer_code to be set.	—
26	`transferred_sw_allow`	smallint measured in bbl/d	221	`WM-TSWA`	East Texas field only: a daily oil allowable added to the well's top allowable, already included in its daily allowable.	—
27	`exempt_gas_transfer`	smallint measured in MCF/d	222-223	`WM-EGT`	Daily gas transferred to or from the well, exempt from the production factor.	—
28	`earned_sw_allow`	smallint measured in bbl/d	224	`WM-ESWA`	East Texas field only: an earned saltwater daily oil allowable, included in the well's daily allowable.	—
29	`acres`	numeric measured in acres	225-227	`WM-ACRE`	Acres assigned to the well for the month, three whole numbers and two decimals, used where acres are part of the allocation formula. Non-zero on 1,933,534 rows; the largest is 997.69.	—
30	`potential`	numeric measured in bbl/d	228-230	`WM-POTE`	The well's working potential in barrels per calendar day, four whole numbers and one decimal, from the test or calculated from production. 9999.9 means the real figure was rounded into the well record's frozen_potential (or perf, for Yates and Hastings West); no row of the August 2026 tape carries the sentinel.	—
31	`bhp_or_acft`	integer	231-233	`WM-ACFT`	Either the well's bottom-hole pressure or its acre-feet, whichever the field rules require -- which is seldom: non-zero on 1,633 of 2,905,616 rows.	—
32	`gor`	integer measured in cf/bbl	234-236	`WM-GOR`	The well's gas-oil ratio in cubic feet per barrel, used in every allowable calculation to decide whether production should be penalised. Zero where the ratio was never reported.	—
33	`oil_transfer_code`	smallint	237	`WM-OTRAN-CD`	Whether an allowable was transferred: 1 to the well, 2 from the well (616 rows), 3 no transfer but the allowable is not cut. The transfer amounts are ignored without it.	—
34	`prorated_oil_transfer`	smallint measured in bbl/d	238-239	`WM-POT`	Daily barrels transferred to or from the well, on top of its regular oil allowable and subject to the production factor.	—
35	`exempt_oil_transfer`	smallint measured in bbl/d	240-241	`WM-EOT`	Daily barrels transferred to or from the well, exempt from the production factor.	—
36	`change_status_code`	smallint	242	`WM-JOHN`	What became effective this month, which protects the allowable from reduction for three months: 1 a new allowable, 2 a new potential, 3 a new gas-oil ratio, 4 GOR and potential, 5 GOR and allowable, 6 potential and allowable, 7 all three (731,304 rows).	—
37	`ooip`	integer measured in bbl	243-248	`WM-OOIP`	Original oil in place in the reservoir the well produces from, in barrels. Zero in every row of the August 2026 tape.	—

Code lookups used here

Every coded column in this dataset resolves to a real lookup table, so a well code of G can be read as what it actually means.

RRC district (proration ledger spelling) 14 values

Read by district, district, district, district, district, district, district, district

The district as the oil and gas proration ledger tapes write it, which is NOT how the rest of the corpus writes it. The ledger pads the lettered districts to three bytes -- 06E, 07B, 07C, 08A -- where the W-10, the G-10 and PDQ's district_name write 6E, 7B, 7C and 8A. That difference is worth a code set of its own because it is invisible in a join: a query matching ledger.district against w10.district returns rows for the ten numeric districts and silently drops the four lettered ones, which are 24% of the oil ledger's wells. Strip the leading zero before joining, or add it coming the other way. `canonical_value` is the internal district number, the same convention rrc.district uses, so a ledger district resolves to the same district in either numbering.

RRC district (proration ledger spelling) — 14 codes and their meanings
Code	Means
`01`	District 01 — San Antonio Written 01 here and 01 elsewhere.
`02`	District 02 — San Antonio Written 02 here and 02 elsewhere.
`03`	District 03 — Houston Written 03 here and 03 elsewhere.
`04`	District 04 — Corpus Christi Written 04 here and 04 elsewhere.
`05`	District 05 — Kilgore Written 05 here and 05 elsewhere.
`06`	District 06 — Kilgore Written 06 here and 06 elsewhere.
`06E`	District 6E — Kilgore The ledger writes 06E; the W-10 and PDQ write 6E.
`07B`	District 7B — Abilene The ledger writes 07B; the W-10 and PDQ write 7B.
`07C`	District 7C — San Angelo The ledger writes 07C; the W-10 and PDQ write 7C.
`08`	District 08 — Midland Written 08 here and 08 elsewhere.
`08A`	District 8A — Midland The ledger writes 08A; the W-10 and PDQ write 8A.
`08B`	District 8B — reserved The manuals list 08B as reserved for future use. No record of any ledger tape has ever carried it.
`09`	District 09 — Wichita Falls Written 09 here and 09 elsewhere.
`10`	District 10 — Pampa Written 10 here and 10 elsewhere.

Source: RRC manuals OLA013K, GSA020K and OLA028K (DIST/DIST-NO items); the thirteen spellings in use confirmed as the complete distinct set in texas.oil_ledger_field, texas.oil_ledger_well and texas.oil_detail_well on 2026-08-21

What this joins to

The Railroad Commission never states these keys anywhere in the files. They are the reason the data is hard to use, so here they are with the exact columns on both sides.

Oil Ledger joins to Oil Ledger — Field Months on District and Field number — one row here matches many rows there.

has fourteen months of allocation factors

The F-MONTH group of the field record, one row per month. All 5,000 sampled fields have all fourteen: the group is fixed-length and the loader keeps a slot only when it carries a cycle stamp, so fourteen of fourteen means the tape filled every one.

oil-ledger.district = oil-ledger-field-months.district AND oil-ledger.field_no = oil-ledger-field-months.field_no

Oil Ledger joins to Oil Ledger — Leases on District and Field number — one row here matches many rows there.

contains the leases

The LEASE records that follow a field record on the tape. Only 1,897 of 5,000 sampled fields have any: two thirds of the 33,939 field records are fields nothing is currently produced from, and they are carried anyway because the schedule is a register of fields, not of production.

oil-ledger.district = oil-ledger-leases.district AND oil-ledger.field_no = oil-ledger-leases.field_no

Oil Ledger joins to Oil Ledger — Wells on District and Field number — one row here matches many rows there.

contains the wells

Every scheduled oil well in the field. 1,582 of 5,000 sampled fields have at least one; the rest have no leases either, or have only multi-well groups, whose wells are on the detail-well tape.

oil-ledger.district = oil-ledger-wells.district AND oil-ledger.field_no = oil-ledger-wells.field_no

Oil Ledger joins to PDQ Field Directory on Field number — one row here matches one row there.

is the field

The ledger's field number resolved to the field directory, which is where the field's name and class live. Measured over the whole table rather than a sample, because 33,939 rows can afford it: all 33,939 field records match a directory entry. District is deliberately not in the join, and it costs nothing to leave out. Field numbers are unique on this tape -- 33,939 numbers in 33,939 rows, none carried in two districts -- and the directory names the same district on every one of them, so adding it would neither narrow the join nor drop a row. Leaving it out also spares the reader the 06E-to-6E translation every other PDQ join here needs. These two columns are different types — one is text, the other an integer — so a direct equality is rejected by Postgres. Cast the text side to integer, which also disposes of any leading zeros; casting the integer to text would not, because '000123' and 123 are not equal as text.

oil-ledger.field_no = pdq-field-directory.field_no

Oil Ledger joins to Oil Ledger — Multi-Well Groups on District and Field number — one row here matches many rows there.

contains the multi-well groups

The waterflood and secondary-recovery units in the field. Rare by design: 107 of 5,000 sampled fields have one, and there are 3,713 groups against 207,544 individually scheduled wells.

oil-ledger.district = oil-ledger-multiwell-groups.district AND oil-ledger.field_no = oil-ledger-multiwell-groups.field_no

Oil Ledger joins to Gas Ledger on District and Field number — one row here matches one row there.

is the gas half of the oil field

A gas field associated with an oil field usually carries the same field number, so the two ledgers meet on it. 1,198 of 5,000 sampled gas fields have an oil ledger record with the same district and number -- close to the 10,287 of 42,133 the gas tape itself marks field_type = 'A' for association. Both sides spell the district the same way, so nothing needs normalising here.

gas-ledger.district = oil-ledger.district AND gas-ledger.field_no = oil-ledger.field_no

Where this comes from

Published by

Texas Railroad Commission — the original page

Original format

EBCDIC IBM mainframe encoding (cp037). Opening it as text gives you nonsense; it has to be transcoded first.

RRC publishes

Updated once a month (Monthly. Available by the 20th.)

RRC download link

GoAnywhere MFT

Record layout manual

OLA013K — Oil Ledger — Record Layout

Our table

texas.oil_ledger_field

EZRRC is an independent mirror of public-domain data published by the Texas Railroad Commission. It is not affiliated with or endorsed by the RRC. For any legal or regulatory purpose, verify against the official RRC release.

Get the data

What this is

What you can do with it

Gotchas

Record layout

oil_ledger_field 53 columns

oil_ledger_field_month 13 columns

oil_ledger_lease 41 columns

oil_ledger_lease_month 25 columns

oil_ledger_multiwell 25 columns

oil_ledger_multiwell_month 28 columns

oil_ledger_well 41 columns

oil_ledger_well_month 37 columns