Description

OCC reports the person's primary occupation, coded into a contemporary census classification scheme (some non-occupational activities are also recorded in the pre-1940 samples). Generally, the primary occupation is the one from which the person earns the most money; if respondents were not sure about this, they were to report the one at which they spent the most time. Unemployed persons were to give their most recent occupation. For persons listing more than one occupation, the samples use the first one listed.

Universe Note: "New Workers" are persons seeking employment for the first time, who had not yet secured their first job.

Note Regarding Multi-Year Samples: In Multi-Year ACS files, OCC codes are based on the year that the file was publicly released (see YEAR). For example, in the 2011-2015 5-year ACS sample, the OCC codes for respondents in 2011 were crosswalked by the Census Bureau to the set of OCC codes used in 2015 to create a single vintage of the occupation variable. See the Industry and Occupation Code Lists and Crosswalks page on the Census Bureau's website for more guidance on how codes are matched across years.

OCC is a 4-digit variable reporting the person's primary occupation, coded into a contemporary census classification scheme (some non-occupational activities are also recorded in the pre-1950 samples). Generally, the primary occupation is the one from which the person earns the most money; if respondents were not sure about this, they were to report the one at which they spent the most time. Unemployed persons were to give their most recent occupation. For persons listing more than one occupation, the samples use the first one listed. OCC specific variable codes for missing, edited, or unidentified observations, observations not applicable (N/A), observations not in universe (NIU), top and bottom value coding, etc. are provided below if applicable by Census year (and data sample if specified).

OCC Specific Variable Codes
See links below for details regarding OCC codes:
1880 Occupation Codes (used for 1850-1900 samples)
1920 Occupation Codes (used for 1910-1920 samples)
1930 Occupation Codes
1940 Occupation Codes
1950 Occupation Codes - see OCC1950
1960 Occupation Codes
1970 Occupation Codes
1980 Occupation Codes
1990 Occupation Codes
2000 Occupation Codes
ACS/PRCS Occupation Codes - 2000-2017
ACS/PRCS Occupation Codes - 2018-present

Comparability

Census practice on collecting occupational data (in OCC) for persons not currently in the labor force changed over time. In the earliest samples, no time referent was specified for when the person was gainfully employed. In 1900, past occupation was specifically requested for persons unable to secure any work during the preceding year, but not for persons who had permanently retired. Similarly, for the 1910-1930 surveys, occupation was to be reported for persons temporarily unemployed, but not for those who had permanently retired.

This changed markedly in 1940 and 1950. In those years, OCC was reserved for those in the labor force (working, with a job, or looking for work) in the week prior to the census. For 1940 and 1950, past occupation was separately collected via different questions and variables (UOCC and ROCC) for formerly-employed persons not currently in the labor force.

1960 marked another turning point, setting the practice for all subsequent years. Beginning in 1960, data on occupation (in OCC), industry (in IND), and class of worker (in CLASSWKR) was collected for all persons of a given age who had worked during a specific and lengthy reference period. For 1960-1970, the reference period was the preceding 10 years; for 1980 on, the reference period was the preceding five years.

The meaning of the OCC codes differs by year and, in 2000, by sample (See Codes and Frequencies). In 2000, the Census Bureau suppressed about 7 percent of the occupation codes in the 5 percent sample. Instead of coding these occupations individually, as they did in the 1 percent sample for 2000, the Bureau included the suppressed occupations in other categories. Also, starting in 2000, the Bureau identified the person's primary occupation which is denoted in the OCCSOC variable. The correspondence between the OCC and OCCSOC codes in the 2000 census samples is recorded in a 2000 census crosswalk. The same correspondence for the ACS samples is recorded in an ACS and PRCS crosswalk.

For all years except 1850-1910, occupations are classified according to the contemporary Census Bureau classification system (the 1930 sample also includes an alpha-numeric classification in OCC1930). In 1850-1900, occupations are classified according to the 1880 system. The 1880 occupational classification was oriented more to work settings and economic sectors - what is now termed "industry" - than to workers' specific technical functions. In 1910, occupations are classified according to the 1920 system. The 1920 classification incorporates function as well as setting and sector, and is very detailed. By 1930, the census generally equated occupation with workers' functions, and relegated work setting and economic sector to a separate industry variable. The variables IND (available for the 1910-2000 censuses and the ACS) and IND1950 (available for all years in the IPUMS) classify work in this way. The methodology used in coding occupations for specific years is discussed in "Occupation Coding Guidelines."

In 1850-1880, any laborer with no specified industry in a household with a farmer is recoded into farm labor. In 1860-1900, any woman with an occupational response of "housekeeper" enters the non-occupational category "keeping house" if she is related to the head of household. Cases affected by these imputation procedures are identified by an appropriate data quality flag.

To increase comparability over time, the IPUMS provides OCC1950 and OCC1990, which apply common classification systems over time. These variables are discussed at length in " Integrated Occupation and Industry Codes and Occupational Standing Variables in the IPUMS."

The term "labor force" and other key employment concepts are defined in the documentation for EMPSTAT and LABFORCE.

User Notes: Enumerator instructions for occupation were often quite long and complicated. The specific wording of the instructions in a given year may affect how particular groups (e.g., women, children, retirees) were enumerated.

Users should also note the changing universe of persons subject to the occupation question (e.g., the rising minimum ages). Persons currently in the armed forces are out of the universe for OCC from 1960 to 1980, yet persons may still report an occupation in the armed services if they are not in the labor force but their last job (within 5 or 10 years) was in the military.

In 1850-1880 and 1900, some enumerators collected information for non-universe persons that is preserved in those samples and hence in the IPUMS version of OCC.

In the 1910 and 1920 Puerto Rico samples, the OCC and OCC1950 variables are derived from different underlying variables and should be treated as independent from one another.

Universe

Availability

• 2023: All samples
• 2022: All samples
• 2021: All samples
• 2020: All samples
• 2019: All samples
• 2018: All samples
• 2017: All samples
• 2016: All samples
• 2015: All samples
• 2014: All samples
• 2013: All samples
• 2012: All samples
• 2011: All samples
• 2010: ACS; ACS 3yr; ACS 5yr
• 2009: All samples
• 2008: All samples
• 2007: All samples
• 2006: All samples
• 2005: All samples
• 2004: All samples
• 2003: All samples
• 2002: All samples
• 2001: All samples
• 2000: All samples
• 1990: All samples
• 1980: All samples
• 1970: All samples
• 1960: All samples
• 1950: All samples
• 1940: All samples
• 1930: 1%; 5%
• 1920: 1%
• 1910: 1%; 1.4% ovrsmp
• 1900: 5%; 1%; 1.2% ovrsmp
• 1880: All samples
• 1870: All samples
• 1860: 1.2%; 100%
• 1850: All samples

• 2023: All samples
• 2022: All samples
• 2021: All samples
• 2020: All samples
• 2019: All samples
• 2018: All samples
• 2017: All samples
• 2016: All samples
• 2015: All samples
• 2014: All samples
• 2013: All samples
• 2012: All samples
• 2011: All samples
• 2010: PRCS; PRCS 3yr; PRCS 5yr
• 2009: All samples
• 2008: All samples
• 2007: All samples
• 2006: All samples
• 2005: All samples
• 2000: All samples
• 1990: All samples
• 1980: All samples
• 1970: All samples
• 1930: --
• 1920: All samples
• 1910: All samples

Flags

Editing Procedure

OCC (Occupation), IND (Industry), and CLASSWKR (Class of worker)
ACS Years: 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015
ACS editing procedure:
The ACS asks a series of interrelated questions about a person's job, including what class of worker they are (eg, private for profit, not-for -profit, government, etc), their occupation, and information about their employer.
Note: OCC and IND are also edited and allocated with the earnings variables. See INCWAGE for more editing and allocation procesures.
First, for everyone who is under 16 OCC, IND, and CLASSWKR will all be "Not in Universe." For anyone who last worked 5 or more years ago and is unemployed or not in the labor force (EMPSTAT, WORKEDYR), OCC, IND, and CLASSWKR will all be "Not in Universe."
The editing of these variables begins by making sure the reported occupation (OCC), employment status (EMPSTAT), industry (IND), and class of worker (CLASSWKR) are all consistent with each other. For example, if EMPSTAT reports that a person is in the military, IND will be edited to "Military" and CLASSWKR will be edited to "Federal Government." Likewise, if a person reports their occupation as "Postal Clerk" but the industry is not "Postal service" the occupation will be changed to "Mail clerks except postal service." There are many similar changes that are not reported here for brevity's sake.
Among those who report themselves as employed (EMPSTAT), self-employed (CLASSWKR), and who are not in the military, occupation (OCC) will be used to make sure the appropriate industry (IND) was selected. For example, a self-employed "Groundskeeper" will have an industry value of "Landscaping services." There are many similar changes that are not reported here for brevity's sake.
If a person is employed, but leaves their industry blank, occupation will be used to infer industry. For example, if a person reports being a "Funeral director" but has no reported industry, IND will be replaced with "Funeral homes." There are many similar changes that are not reported here for brevity's sake.
If a person is older than 15, is employed (EMPSTAT), but occupation is missing, the reported industry (and sometimes class of worker) will be used to determine occupation. For example, if a person's industry is "Agricultural production" and their class of worker is "Self-employed not incorporated," OCC will be replaced with "Farmers." If industry if "Forestry" OCC will be replaced with "Forestry workers except logging." There are many similar changes that are not reported here for brevity's sake.
If a person is older than 15, is employed (EMPSTAT), industry will be used to assign or change the class of worker. For example, if IND is "Postal service," class of worker will be made "Federal government." There are many similar changes that are not reported here for brevity's sake.
Farming
If a person is 16 or 17 and reports their occupation as "Farm manager or farmer," OCC will be replaced with "Agricultural worker." If a person is 16 or 17 and their occupation is "Supervisors, farming, fishing, and forestry workers" and their class of worker is not "Private" or "Government," CLASSWKR will be replaced with "Private for profit
Among those 18 and older whose occupation is "Farm, ranch, and agricultural managers" and who are self-employed (CLASSWRK), OCC will be changed to "Farmer." If CLASSWRK is "Without pay family," OCC will be replaced with "Farmer" and CLASSWRK will be "Self-employed not incorporated." If CLASSWRK is not reported, it will be replaced with "Private for profit."
Among those 18 and older whose occupation is "Farmer" and class of worker is "Private" "Government" or "Self-employed incorporated", OCC will be made "Farm, ranch, and agricultural managers." If CLASSWKR is not reported or "Without pay family" CLASSWKR will be replaced with "Self-employed not incorporated"
Among those 18 and older whose occupation is "Supervisors, farming, fishing, and forestry workers" and industry is 0170 or 0180 (Census original codes - unclear what industries these are) and CLASSWKR is "Self-employed not incorporated," OCC will be replaced with "Farmers." If CLASSWKR is " Self-employed incorporated," OCC will be replaced with "Farm, ranch, and agricultural managers." If CLASSWKR is not reported or is "Without pay family," CLASSWKR will be replaced with "Private for profit."
Among those 18 and older whose occupation is "Farm workers" and CLASSWKR is "Self-employed not incorporated," OCC will be replaced with "Farmers." If CLASSWKR is " Self-employed incorporated," OCC will be replaced with "Farm, ranch, and agricultural managers." If CLASSWKR is not reported, it will be replaced with "Private for profit."
Education and Earnings to adjust OCC and IND
Education and earnings are also used to edit the occupation and industry. If a person with an education (EDUC) that is lower than required by a specific occupation (eg, someone with less than high school who reports being an "Accountant or auditor") and also reports low weekly earnings (INCWAGE, WKSWORK2), the occupation will be changed to a related field that is more consistent with the reported education (eg, "Bookkeepers, accounting, and auditing clerks"). There are many similar changes that are not reported here for brevity's sake.
Military adjustments
If a person who is 16 or older reports their industry as "Military" but their occupation is inconsistent with the Armed Forces, their occupation will be adjusted. For example, if a person in the military reports being a "Legislator," OCC will be replaced with a rotation of "General and operations managers" and "Mangers, all other." There are many similar changes that are not reported here for brevity's sake.
If a person reports not being active duty military (VETSTAT), but reports their industry as "Active duty military," IND will be changed to "National security and international affairs." Their OCC value will also be adjusted to a similar non-military value if they report being a "Military officer" or "Other military." In 2007 and later, whose employment status (EMPSTAT) is "Civilian labor force" reports their industry as "Military," IND will be changed to "National security and international affairs." In 2007 and later, if a person under 17 reports their occupation (OCC) or industry (IND) as "Military," their OCC will be changed to "Miscellaneous office and administrative support workers, including desktop publishers" and IND to "National security and international affairs."
Adjusting earnings
If a person is 16 or older, reports working in the past 12 months, and is self-employed not incorporated (CLASSWKR), and has positive wages (INCWAGE) but no self-employment income (INCBUS00), their value for INCWAGE and INCBUS00 will be swapped.
If a person is 16 or older, reports working in the past 12 months, and is not self-employed not incorporated (CLASSWKR), and no positive wages (INCWAGE) but positive self-employment income (INCBUS00), their value for INCWAGE and INCBUS00 will be swapped.
If a person is 16 or older, reports working in the past 12 months, and is not self-employed not incorporated (CLASSWKR), and no positive wages (INCWAGE) and negative self-employment income (INCBUS00), CLASSWKR will be replaced with "Self-employed not incorporated."
Flags
The flag variables (QOCC, QIND, QCLASSWK) will indicate when the values of OCC, IND, and CLASSWKR are allocated.
Internal ACS variable : OCC IND COW