pretty_name: >-
WARN Act notice-type codes crosswalk - every raw state string and what it
means
license: cc-by-4.0
language:
- en
task_categories:
- tabular-classification
- text-classification
tags:
- warn-act
- data-cleaning
- entity-resolution
- normalization
- crosswalk
- codebook
- data-dictionary
- layoffs
- layoff-notices
- plant-closings
- labor
- labor-market
- public-records
- government-data
- daily-updated
- united-states
size_categories:
- n<1K
configs:
- config_name: crosswalk
data_files: data/notice_type_crosswalk.csv
WARN Act notice-type codes — the crosswalk
Every US state publishes WARN Act layoff notices with a free-text column saying what kind of event it is. The statute recognises two: a plant closing and a mass layoff. Across 48 states that column contains 552 distinct exact strings (531 once you fold case).
This dataset is the crosswalk: one row per raw string, how many notices carry it, which states emit it, and what it normalizes to.
The finding that matters
521 of the 552 strings (94%) are used by exactly one state. Only 31 are shared across states at all.
There is no common vocabulary. CL means closure in Indiana and Wisconsin;
Illinois fills the column with State; five states write WARN — the name of the
statute — where the event type belongs. 372 strings appear on a
single notice in the entire archive.
This is why "just parse the state files" does not converge: there is nothing to parse toward until someone reads all 48 vocabularies and keeps reading them as states change their exports.
Vocabulary by what it maps to
| maps to | distinct strings |
|---|---|
| layoff | 185 |
| closure | 147 |
| mixed (both terms present) | 23 |
| unknown (deliberately unmapped) | 197 |
unknown is a real category, not a failure to try. It covers blanks, strings that
name which statute applies rather than what happened (State, WARN, numeric
record codes), and strings that name a cause (loss of contract, sale of company, COVID-19) rather than an event. Guessing these would manufacture
thousands of false rows that no downstream user could detect.
The 12 most common strings
| raw value | maps to | notices | states | used by |
|---|---|---|---|---|
| (blank) | unknown | 13,759 | 29 | AK CO CT DC FL HI ID KY LA MA MN MO MT ND… |
Layoff Permanent |
layoff | 7,812 | 2 | CA TN |
Closure |
closure | 6,077 | 15 | AK AL CO KY MI MS NC NE NV NY OH PA VA WA WV |
Layoff |
layoff | 5,943 | 15 | AK AL KY MI MO MS NC NE NV NY OH PA VA WA WV |
State |
unknown | 4,845 | 1 | IL |
Closure Permanent |
closure | 4,164 | 2 | CA TN |
Layoff Temporary |
layoff | 3,657 | 2 | CA TN |
WARN |
unknown | 1,658 | 5 | AZ DE KS ME VT |
Plant Closing |
closure | 1,398 | 4 | MI NY OK PA |
Closing |
closure | 1,196 | 8 | CO CT IA MN MO PA RI WV |
CL |
closure | 862 | 2 | IN WI |
Mass Layoff |
layoff | 838 | 8 | CO IA MD MI NY OK PA WV |
Files
data/notice_type_crosswalk.csv— 552 rows:raw_value,kind,permanence,reason,notices,n_states,states.
Covers all 61,304 notices in the archive as of 2026-09-13; rebuilt daily in the same pipeline run as the notices themselves, so the two can never disagree.
Limits — read before citing
- These are notices, not verified job losses. A WARN notice can be amended, rescinded, or never carried out.
- The mapping is conservative: anything that does not clearly say closing or
layoff is left
unknownrather than guessed. permanenceis only populated where the state says so; most states do not.- Counts are of notices, not workers.
Related
- Daily US WARN notices (flagship) — the full normalized feed
- Plant closings vs mass layoffs — this mapping applied
- Site · Source and methodology
License CC-BY-4.0. Built from public state government records.