LABOR FORCE STATISTICS FROM THE CURRENT POPULATION SURVEY (LN database)
				ln.txt

Section Listing

1. Survey definition
2. Flat files listed in the survey directory
3. Series file, data file, mapping file, and aspect file definitions and relationships
4. Series file format 
5. Data file format and field definitions
6. Mapping file formats and field definitions
7. Aspect file format and field definitions


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Section 1 - Survey definition
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Survey description:

The labor force statistics (LN) database provides information from the Current Population Survey (CPS), 
frequently referred to as the household survey, that provides information on the labor force status, demographics, 
and other characteristics of the nation's civilian noninstitutional population age 16 and over. The survey is 
conducted monthly for the Bureau of Labor Statistics (BLS) by the U.S. Census Bureau from a scientifically 
selected national sample of about 60,000 eligible households in the 50 states and the District of Columbia. 
Data generally refer a person’s status in the survey reference week, usually the 7-day calendar week (Sunday–Saturday)
that includes the 12th of the month.

Summary data available: CPS data are available for the civilian noninstitutional population age 16 
and older and various detailed groups, with estimates available by age, race, sex, Hispanic or Latino
ethnicity, employment status, occupation, industry, class of worker (self-employment status), educational attainment,
telework status, and other characteristics.

Frequency of observations: LN series are produced as monthly, quarterly average, and annual average series. 
There are many related series that differ only by periodicity. Some monthly data series are seasonally adjusted; 
when a seasonally adjusted series exists in the database, a not seasonally adjusted series also is present. 
Annual averages are stored with monthly not seasonally adjusted series. Nearly all monthly series also have a related
series with quarterly averages. About 40 percent of the series in the LN database are series with only annual averages

Data characteristics: Data include counts of people (presented in thousands) and rates such as the unemployment rate,
labor force participation rate, and employment-population ratio. (Rates and ratios are expressed as percents with 
one decimal place.) Information is also available on hours worked for the employed and the duration of unemployment.

Updating schedule: The LN database is updated monthly with the issuance of the monthly 
Employment Situation news release. (The schedule is online at https://www.bls.gov/schedule/news_release/empsit.htm.) 
Quarterly estimates are available with the publication of the last month in the quarter. 
Annual averages are available with the December estimates.

Most CPS estimates are considered final when published and are not subject to routine revision. A small portion of CPS 
times series are seasonally adjusted. At the end of each calendar year, BLS reestimates the seasonal factors for the 
CPS series by including another full year of data in the estimation process. Following this annual reestimation, 
BLS revises the historical seasonally adjusted data for the previous 5 years. Not seasonally adjusted data are 
considered final when published. (Learn more about seasonal adjustment at https://www.bls.gov/cps/documentation.htm#sa.)

Additional information about the CPS is available at https://www.bls.gov/cps/documentation.htm.

The LN database is one of several databases containing information from the CPS. Other databases have information on 
earnings, union membership, and other topics. Learn more at https://www.bls.gov/cps/data.htm.

If you have questions about these data, please contact staff via email at CPSInfo@bls.gov


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Section 2 - Flat files listed in the survey directory
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The following CPS labor force files are on the BLS internet in the 
sub-directory https://download.bls.gov/pub/time.series/ln/:

       ln.absn			- Absence codes 					mapping file
       ln.activity		- Activity (school enrollment) codes 			mapping file
       ln.ages			- Age group codes 					mapping file
       ln.aspect		- Standard errors for data				data file
       ln.born			- Native/foreign born codes 				mapping file
       ln.cert			- Certification/licensing codes 			mapping file
       ln.chld			- Presence of children codes 				mapping file
       ln.class			- Class of worker codes 				mapping file
       ln.data.1.AllData	- All data						data file
       ln.disa			- Disability codes 					mapping file
       ln.duration 		- Duration codes 					mapping file
       ln.education 		- Education codes 					mapping file
       ln.entr 			- Unemployed new entrants/reentrants codes 		mapping file
       ln.expr	 		- Experienced unemployed codes 				mapping file
       ln.footnote 		- Footnote codes 					mapping file
       ln.hheader 		- Women who maintain families (family heads) codes 	mapping file
       ln.hour	 		- Hours worked codes 					mapping file
       ln.indy	 		- Industry codes 					mapping file
       ln.jdes	 		- Want a job codes 					mapping file
       ln.lfst	 		- Labor force status codes 				mapping file
       ln.look	 		- Job seeker codes 					mapping file
       ln.mari	 		- Marital status codes 					mapping file
       ln.mjhs	 		- Multiple jobholder codes 				mapping file
       ln.occupation 		- Occupation codes 					mapping file
       ln.orig	 		- Hispanic or Latino ethnicity codes 			mapping file
       ln.pcts	 		- Percentage codes 					mapping file
       ln.periodicity 		- Periodicity codes 					mapping file
       ln.race	 		- Race codes 						mapping file
       ln.rjnw	 		- Absence reason codes 					mapping file
       ln.rnlf	 		- NLF job search and reason codes 			mapping file
       ln.rwns	 		- Part time reason codes 				mapping file
       ln.seasonal 		- Seasonal adjustment codes 				mapping file
       ln.seek	 		- Job seeker codes 					mapping file
       ln.series		- All series with titles and beginning and end dates
       ln.sexs	 		- Sex codes 						mapping file
       ln.tdat	 		- Data type codes 					mapping file
       ln.tlwk	 		- Telework codes 					mapping file
       ln.txt			- General information
       ln.vets	 		- Veteran status codes 					mapping file
       ln.wkst	 		- Work status codes 					mapping file

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Section 3 - Series file, data file, mapping file, and aspect file definitions and relationships
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The flat files are organized such that data users are provided with the following
set of files to use in their efforts to interpret data files:

a) a series file (only one series file per database)
b) mapping files
c) a data file
d) an aspect file

The series file contains series identification codes that serve to uniquely identify 
time series within the database, along with their titles and attributes (age, sex, race, 
occupation, industry, etc.). The series file contains the following 
series-level information:

a) a series identification code
b) a series title
c) characteristics of the series corresponding to values in the mapping files
d) the period and year corresponding to the first data observation 
e) the period and year corresponding to the most recent data observation 

The mapping files are definition files that contain explanatory text 
descriptions that correspond to each of the various attributes associated with 
the database and referenced in the series file.

The data file contains one line of data for each observation period pertaining
to a specific time series. Each line contains a reference to the following:

a) a series identification code
b) the year in which data is observed
c) the period for which data is observed (M01 to M12 indicate monthly data, 
A01 and M13 indicate annual averages, and Q01, Q01, Q03, Q04 indicate quarterly averages)
d) a value
e) footnote codes (if available)

The aspect file contains one line of data (standard error) for each observation period pertaining to 
a specific time series. Each line contains a reference to the following:

a) a series identification code
b) the year in which the standard error is observed
c) the period for which the standard error is observed
d) aspect type (E indicates standard error)
d) a value of the standard error
e) footnote codes (if applicable)

For series that have monthly data, M13 indicates annual averages. For series that do
not have monthly data, A01 indicates annual averages. The quarterly series in the LN database 
do not contain annual averages; the annual average is stored with the equivalent monthly series.

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Section 4 - Series file format
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File Structure and Format: The following represents the file format used to 
define ln.series. Data files are in ASCII text format. Data elements 
are separated by tabs; the first record of each file contains the column headers 
for the data elements stored in each field. Each record ends with a new line 
character. 

The series file contains series identification codes that serve to uniquely identify 
time series within the database, along with their titles and attributes (age, sex, race, 
occupation, industry, etc.). The series file contains the following series-level information:

a) a series identification code
b) a series title
c) characteristics of the series corresponding to values in the attribute mapping files
d) the period and year corresponding to the first data observation 
e) the period and year corresponding to the most recent data observation 

Series ID Structure and Format:
In the LN database, series ID codes cannot be decoded to refer to specific data types by looking at 
the value of different components of the series code. The LN database has too many attributes 
to assign each position of the series ID code to a specific attribute value. The only meaningful 
values are the initial positions where LNS identifies a seasonally adjusted series and LNU identifies a not 
seasonally adjusted series. The other values in the series ID code cannot be broken down into meaningful 
components. You must use the ln.series file (which includes descriptive titles) to determine the attributes 
that define a specific series.


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Section 5 - Data file format and field definitions
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Data File Structure and Format: The following represents the file format used to 
define the data file. Note that the field numbers are for reference only; they 
do not exist in the database. Data files are in ASCII text format. Data 
elements are separated by tabs; the first record of each file contains the 
column headers for the data elements stored in each field. Each record ends 
with a new line character.

The ln.data file is stored in one file: ln.data.1.AllData
The data file contains one line of data for each observation period pertaining 
to a specific time series. Each line contains a reference to the following:

a) a series identification code
b) the year in which data is observed
c) the period for which data is observed (M01 to M12 indicate monthly data, 
A01 and M13 indicate annual averages, and Q01, Q01, Q03, Q04 indicate quarterly averages)
d) a value
e) footnote codes (if available)

Field #/Data Element		Length		Value (Example)	

1. series_id			varies		LNU04000000

2. year				4		2026	

3. period			3		M04	

4. value			12		4.0	

5. footnote_code (if available)	2		(blank)	


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Section 6 - Mapping file formats and field definitions
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Mapping File Structure and Format: The following represents the file format used to 
define each mapping file. Note that the field numbers are for reference only; they 
do not exist in the database. Mapping files are in ASCII text format. Data elements 
are separated by tabs. The first record of each file contains the column headers 
for the data elements stored in each field. Each record ends with a new line character. 

Each mapping file follows a similar format:

Field #/Data Element		Length		Value 

1. characteristic code 		varies		typically a numeric value

2. characteristic text		varies		typically a text description


For example, the ln.ages mapping file contains one header row and 35 rows of value entries. 
The ages_code of 00 represents people 16 years and over.

Field #/Data Element		Length		Value (Example)
1. ages_code			2		00

2. ages_text			17		16 years and over

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Section 7 - Aspect file format and field definitions
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Aspect File Structure and Format: The following represents the file format used to 
define the aspect file. Note that the field numbers are for reference only; they do 
not exist in the database. The aspect file is in ASCII text format. Data elements are 
separated by tabs. The first record of each file contains the column headers for 
the data elements stored in each field. Each record ends with a new line character.


The aspect file has the following format:

Field #/Data Element			Length		Value (Example)	

1. series_id				varies		LNU04000000

2. year					4		2026	

3. period				3		M04	

4. value				12		0.11	

5. footnote_codes (if available)	2		(blank)


The aspect file contains standard errors for values in the data file. These standard errors 
provide measures of precision for CPS labor force estimates and facilitate comparisons 
with other estimates representative of the same time period. They should not be used 
to determine whether 1-, 3-, 6-, or 12-month changes are statistically significant.
Standard errors are available for most series in the LN database. The aspect file 
standard errors are available beginning with data for 2026.

Learn more about when it is appropriate to use these standard errors and the reliability 
of CPS estimates at https://www.bls.gov/cps/methods/reliability-of-cps-estimates.htm