NLSY79

The following race and ethnicity variables are available for NLSY79 respondents: 

1. a racial/ethnic variable based on the sample identification code assigned by NORC
2. a series of self-reported ethnic origin variables collected during the 1979 and 2002 surveys
3. a set of interviewer identifications of the race of the respondent at the time of the interview
4. racial/ethnic identification for current and past spouse/partners
5. variables representing the respondent's immigration history and status collected during the 1990 survey
6. a 1979 variable indicating whether a foreign language was spoken in the house during the respondent's childhood
7. a series of variables recorded by the interviewer indicating whether the survey was administered in English or another language
8. race/ethnicity variables for each family member listed during the 1978 screener
9. race of the interviewer where available at each interview
10. country of origin of the respondent's parents and the respondent's country of birth, available on the restricted Geocode release

Race and ethnic origin information is also available for each household member identified during the 1978 household screening. In 2002 respondents were asked to identify their race/ethnicity using questions that conformed to Federal government definitions. Of related interest is a series of immigration questions, fielded in 1990, that included the collection of information on country of citizenship at the time that foreign-born respondents entered the U.S.

Race/Ethnicity

The variable 'Racial/Ethnic Cohort from Screener' (R02147.) designates the respondent as "Hispanic," "black," or "nonblack/non-Hispanic" and provides the basis for weighting NLSY79 data. This variable is collapsed from R01736., 'Sample Identification Code,' which includes such values as "supplemental male black" or "cross-sectional female Hispanic." This code was assigned by NORC to each respondent based on information gathered during the 1978 household screening. In the creation of the 'Sample Identification Code' and thus the 'Racial/Ethnic Cohort' variable, both race and ethnic origin information collected at the time of the 1978 household screening were used. Interviewers conducting the screening were instructed to:

1. code race by observation into three categories, "nonblack/non-Hispanic," "black," or "other"
2. inquire about the ethnicity of all household members age 14 or above
3. but assign ethnicity, without asking, to those members who were under age 14

Coding procedures used by NORC to assign the "Hispanic," "black," and "nonblack/non-Hispanic" identifications to respondents included the following classification guidelines:

A series of ethnic identification variables, '1^st-6^th Racial/Ethnic Origin' and 'Racial/Ethnic Origin with Which R Identifies Most Closely' (R00096.-R00102.), provide extensive ethnicity information. Respondents were asked during the 1979 interviews to name the racial/ethnic origins with which they identified.  A listing of more than 20 categories, including "Black," "English," "French," "German," "American Indian," "Irish," "Mexican," "Mexican-American," and "Puerto Rican," were presented on a Show Card. If a respondent offered more than one origin, he or she was also asked for the ethnic group with which he or she most closely identified.  Users should be aware that frequency counts for the coding category "Indian American, or Native American are unusually high.  About 5 percent of respondents reported this racial/ethnic origin, compared to Census estimates of approximately 0.5 percent of the population. This may have resulted from some respondents' misinterpretation of the term "Native American." Table 1 compares frequencies of the 1979 first (or most closely held) ethnic identification with the NORC assigned racial/ethnic identification.

Immigration

In 1990, NLSY79 respondents born outside the United States, its territories, or Puerto Rico were asked a series of questions on their immigration history and visa status. Dates of first and most recent entrance into the United States to live for six or more months and information on whether the respondent was the principal entrant/immigrant were collected. For respondents' or principal entrant/immigrants' first and most recent entry or change in visa/immigration status, details were gathered on:

1. visa or immigration status at entry date
2. form of temporary entry visa
3. citizenship status (that is, citizen or permanent resident alien) and relationship of the sponsoring relative
4. country of citizenship at entry date or date of change of status

Also recorded for the respondent was information on:

1. current citizenship/residence/visa status in the United States
2. residence inside/outside the United States
3. expectations to return to the United States to live permanently or to return to his or her country of birth to live permanently
4. the total number of years spent outside the United States since initial entry

Of related interest is the variable, 'Is R a Citizen of the U.S.' available from the 1984 and 1990 interviews.

Foreign Language Used or Spoken

For each household member, information is available from the screener on presence of a Spanish surname and whether Spanish was the language spoken in the home when that individual was a child. The 1979 interview asked whether a foreign language (Spanish, French, German, other) was spoken at home during the respondent's childhood. In addition, interviews record for each survey whether English, Spanish, or another foreign language was used to administer the Household Interview Forms ('English or Foreign Language Used for Household Record') and questionnaire ('Int Remarks - Was Interview Conducted in English or Foreign Language').

Comparison to Other NLS Cohorts: Race is available for all cohorts; ethnicity is available for all cohorts except the Older Men and Young Men. Users should be aware that coding categories for race and ethnicity have varied among cohorts and over time. For more precise details about the content of each survey, consult the appropriate cohort's User's Guide using the tabs above for more information.

Reference

NORC. 1978 Household Screener and Interviewer's Reference Manual. Chicago, IL: National Opinion Research Center - University of Chicago, 1978.

• This section describes variables related to household and family composition, household identification, linkages between members of multiple respondent households, and household residence.

Household members

The term "household" refers to all individuals sharing the respondent's primary residence at the time of the interview. For respondents living in temporary quarters (except temporary military quarters), the usual residence is defined as that person's permanent residence. For those living in their own dwelling unit or in military family housing, the usual residence is the person's dwelling unit. For example, if a male college student is living in a temporary residence, such as a fraternity, those who share his permanent residence, such as his parents' address, would be considered his household members. However, if that same college student were living in his own apartment, all those living in his apartment would be considered his household members.

Persons analyzing military households should note that household screener information was not collected for persons in the military sample. Thus, while military units are included in the total 8,770 unique households, military units cannot be multiple respondent households. Household specification for those respondents enlisted in the military is as follows: (1) for those in the military who are married but living in military quarters other than military family housing, the household is the household of the respondent's spouse, and (2) for those in the military who are unmarried, no household information is recorded.

During PAPI surveys, information about a respondent's household was gathered during a separately administered household interview. Three different Household Interview Forms "Household Interview Forms" were used prior to 1987: 

• Version A was completed by a parent of those respondents living in a parental household
• Version B was administered to youth not living at a permanent address
• and Version C was answered by those respondents living in their own dwelling unit or independent living quarters

Table 1 details, by survey year, the relevant universes and residence types specific to each version; notes on variations in administration of the forms are included. A series of variables entitled 'Version of Household Record Used' is available for the 1979-80 and 1982-86 survey years. To determine the version of the household interview used in 1981, it is necessary to match information from the variable, 'Type of Residence R is Living In,' to residence information that was included on the three different forms. Beginning in 1987, only one version of the household interview was used, as all respondents were 22 or older and living predominantly on their own. Since the introduction of CAPI interviews in 1993, household information has been collected in the first section of the main questionnaire rather than in a separate instrument.

All members of the respondent's household are enumerated each survey year on the household record; in 1978, household members were listed on the household screener. The relationship generally listed for each household member on the household record is relative to the youth respondent, such as 'Household Record - Relationship to Youth Member # 1.' For variables from the screener and for one series of 1979 household record variables, the relationship of household members (only family members in the screener) is relative to the householder. Anyone who lives in the residence but is temporarily away is listed; anyone who is there only temporarily is removed from the listing. For the screener and for interviews in which the respondent lives in a new household, that is, living with new people rather than living at a new address, the householder generally is listed first, followed by a spouse; any children; any other relatives; and any roomers, boarders, hired help, or other usual unrelated residents.

Family members

Within the listing of household members, family units are identified through family unit numbers and relationship codes. A family unit includes all those related by blood, marriage, or adoption. For each member of the household in every survey year, including the 1978 screener, the family unit number is listed on the "Household Enumeration" or the screener, such as 'Household Record - Family Unit # 1 Member # 1.' All family members in an interrelated group will share a family unit number, with number 1 assigned to the respondent's family. Each additional interrelated group or individual adult sharing the household but not related to another group or individual in the household constitutes an additional family unit. For example, if Mr. and Mrs. Brown are boarders in the same house with Mr. and Mrs. Smith, the Smiths are the first family unit and the Browns are a second family unit. The reliability of 1979-92 family unit numbers beyond those assigned to the respondent's family is questionable. Beginning in 1993, family units were assigned electronically; the definition of a family unit remains the same. Codes were added for partner's family/relations. All others are assigned a code of "9."

An enumeration of a respondent's children is also available. Several variables have been created as part of the Supplemental Fertility File (area of interest "Fertility and Relationship History/Created"), including variables such as '# of Own Children in Household,' 'Age of Youngest Child in Household,' and a variety of variables for each biological child listed, with some exceptions, in order of age. Unedited variables from the Children's Record Form (areas of interest "Child Record Form/Biological" and "Child Record Form/Nonbiological") are also available for both biological and nonbiological children. If there is a discrepancy between household rosters versus marriage event histories use the marriage event histories rather than the household roster data. See the "Fertility" section of this guide for more information about the collection of information on the respondent's children.

Additionally, information about household members includes, sex of the member, their relationship to the respondent, age, highest grade completed, and whether the member receives pay for work (age restrictions apply.)

Finally, information on whether the mother and father of each child (in 1991, new children only) live in the household is available for the 1987-2014 survey years. In all other years, information on whether the father of the child is present is available for children of female respondents.

Family size

Beginning with the 1990 release, a family size variable, comparable to the family size variable created for the computation of the 'Total Net Family Income' and 'Poverty Status' variables, was created for each year. The variable is constructed by simply cycling through the household record "relationship codes" and increasing the family size by one each time a qualifying relationship relative to the respondent is encountered. Qualifying relationships include all relations by blood, marriage, and adoption. Foster relationships, partners, boarders, guardians, and other individuals are not considered family members in the creation of this variable.

Program derivation

The SPSS program statements for a sample survey year (1979-92) FAMILY SIZE variable are as follows:

COUNT FAMSZXX=RELR1 TO RELR15 (0 THRU 32,37 THRU 44,47 THRU 49)

IF (WEIGHTXX EQ 0) FAMSZXX=-5

After 1993, the roster was expanded to accommodate up to 20 individuals. The SPSS program is the same but the number of relationships to check is five larger. Additionally, the respondent is not on the household roster after 1992, so FAMSZXX is initialized to "1."

Household identification and linkages

The NLSY79 screening procedure allowed more than one member of a household to be selected for interviewing. The original 12,686 respondents were members of 8,770 households; 6,742 respondents or 53 percent of the sample were members of households from which more than one respondent originated, while 5,944 respondents or 47 percent were members of single respondent households (Table 2). To establish linkage of respondents originating from the same household, variables identify other interviewed household members and their relationships as of the 1979 interview. The 1979 variable providing the unique household identification number of each household is R00001.49, 'Household Identification Number' (HHID). The same HHID is assigned to all respondents who originated from the same household in 1979. In multiple-respondent households, the HHID corresponds to the lowest respondent 'Identification Code' of all respondents interviewed in that household; in single-respondent households, the HHID corresponds to the respondent 'Identification Code.' The HHID variable was constructed using other created variables from the NLSY79 main data set and exists only for 1979.  Multiple respondent households can also be identified through variables that identify other respondents in the same household and their relationship to the first respondent. Reference numbers include R00001.50-R00001.61, for example, 'Identification Code of 1^st Other Interviewed Youth in R's Household.'

Although these matches represent unique samples for a number of research topics, be aware that matches may be not be demographically representative due to the age restrictions applied to all members chosen from a household. The primary types of relationships that existed among respondents within multiple respondent households at the time the surveys began included brothers, sisters, husbands, and wives (Table 3). Other relationships included cousins, brothers- and sisters-in-law, step-brothers or -sisters, and other types of household members.

Household residence

Household residence refers to the type of dwelling or living situation of the respondent. Household residence information is available for the respondent at each survey point, for the respondent during his or her childhood, and for the respondent's children during recent surveys. The variable 'Type of Residence R is Living In' classifies the respondent's actual place of residence at the time of each survey. From 1979-86, it was created based upon responses to several questions asking about different types of dwelling units. In these years, several versions of the Household Interview Forms (the instrument completed before the main questionnaire and used to construct the household enumeration) existed. The universes for these different versions were dependent upon the type of dwelling unit in which the respondent lived (parental home, own dwelling unit, individual or group quarters), the sample type of the respondent (military or civilian), and who answered the household interview section questions (respondent or parent). The responses to questions designating type of residence from each of these versions were combined into one variable reflecting type of residence for the entire sample.

Beginning in 1987, the several versions of the Household Interview Forms were combined and all types of residences were coded in one question. Therefore, after 1986, this question is no longer considered a "created" variable. The 'Type of Residence R is Living In' variables include categories such as dorm, fraternity or sorority, hospital, jail or juvenile detention center, orphanage, religious institution, own dwelling unit, parents' household, and specific types of military quarters. The codes assigned to response categories for type of residence in 1979 differ significantly from those in other survey years. Also, in earlier years, respondents living in parental homes were treated as valid skips; in later years, these respondents were assigned a separate code that differs by year.

Retrospective information describing the respondent's childhood living arrangements was collected during 1988 in a three-part series of questions on the Childhood Residence Calendar. In Part 1, the respondent's identification of any type of parent with whom he or she lived for four or more months was recorded. Coding categories included biological, adoptive, or stepmother or father for each age from birth through 18 years, for example, 'Lived with Biological Mother at Birth,' 'Lived with Adoptive Father at Age 16.' Ages at which the respondent stopped living with a parent, the reason for ending shared living arrangements, and the frequency of visitation with the absent parent during the first year after coresidence ended were also collected. For those ages when the respondent reported not living with a parent, information was collected in part 2 of the Childhood Residence Calendar on:

• coresidence with grandparent(s), other relative(s), foster parent(s), or friend(s)
• residence in a children's home or orphanage, a group care home, a detention center/jail/prison, or another institution
• use of another type of arrangement
• for those ages ten and over, whether the respondent was left to be on his or her own

Variable titles for this series include 'Lived with Foster Parent(s) (Not Living With a Parent) at Age-7,' 'Lived in Children's Home/Orphanage (Not Living With a Parent) At Age-2,' 'Left to be on Own (Not Living With a Parent) at Age-15.' The number of foster or group care arrangements experienced by the individual is also recorded. Finally, in part 3 of this supplement for each age during which the respondent experienced more than one living arrangement when not living with a parent, the place at which s/he stayed the longest is identified. Data quality issues are discussed by Haurin (1991).

Information on the residence of respondents' children is available, for the most part, since the 1982 survey year. Note that edited variables based on the 1989 and 1991 raw data are not available until the subsequent year's release. These edited variables, cleaned and checked for consistency, include residences of each biological child in birth order (with some anomalies), such as 'Usual Residence of 7^th Child,' and combine information collected for residence of children of male respondents with that of children of female respondents. Coding categories include in the respondent's household, with other parent, with other relatives, in foster care, with adoptive parents, in a long-term care institution, away at school, deceased, lives part-time with both parents, lives part-time with the respondent and another person, and other. The unedited variables upon which the edited variables are based can be found in the "Fertility" section of the main youth questionnaire and include residence of all biological children; residence of all children born by the time of the previous interview, collected annually since 1984; and residence of all children born since the last interview, collected since 1983. Unedited residence information for nonbiological children is available for 1985, 1986, 1988, 1990, 1992, and from 1994 forward. Coding categories for all unedited variables are the same as for edited variables.

References

Haurin, R. Jean. "Childhood Residence Patterns: Evidence from the National Longitudinal Surveys of Work Experience of Youth." Columbus, OH: CHRR, The Ohio State University, 1991.

Morgan, William R. "Sibling Influences on the Career Plans of Male and Female Youth." Columbus, OH: CHRR, The Ohio State University, 1983.

Geographic data for NLSY79 respondents fall into two categories: information on the main public file and more detailed information released as restricted-use Geocode data. Table 1 lists NLSY79 geographic variables along with their areas of interest. Variables with a "Geocode xxxx" area of interest are restricted-use data; all others are public use.

Related Variables: Related NLSY79 main file variables discussed in the  Household Composition and Family Background sections of this guide include:

• Type of residence or dwelling unit at the time of interview (such as dorm, hospital, jail, orphanage, own home, and so forth)
• Childhood living arrangements of NLSY79 respondents from birth to age 18, including not only information on persons with whom the respondent lived (such as biological versus adoptive and step-parents) but also on institutions such as children's homes, group care homes, or detention centers/jails/prisons in which he or she may have resided.

Geocode file variables

• Information on the State, county, and metropolitan statistical area of residence for each respondent (the current residence variables) are merged with information from several other data files, namely the City Reference File (Census 1973, 1982, 1983, 1987, 1992) and the County & City Data Book (Census 1972, 1977, 1983, 1988, 1994), to provide detailed information on the environmental characteristics of the State, county, and metropolitan statistical areas in which each NLSY79 respondent resides. NOTE: Users may attach additional county and metropolitan statistical area-level data from a variety of sources by simply merging information from the desired source with the Geocode data based upon the State, county, and metropolitan statistical area of residence codes in the Geocode file
• For select survey years Geocode information is available on the location of respondents' jobs, the location of colleges attended, and the point of discharge from military service
• Unemployment rate of each respondent's labor market of current residence:
  • The source of the 'Unemployment Rate' variables is the May issue of the Bureau of Labor Statistics' Employment and Earnings for the year following the survey year. Figures from March of each survey year are used. This table supplies unemployment rates for each State and for selected metropolitan statistical areas. Respondents who reside within one of these metropolitan statistical areas are assigned the appropriate unemployment rate. For those residing outside of these areas, a "balance of State" unemployment figure is computed using State total figures for the size of the civilian labor force and the number employed and subtracting the population living in metropolitan statistical areas.
  • Additional information on these variables can be found in Appendix 7 in the NLSY79 Geocode Codebook Supplement.

Types of County or Metropolitan Statistical Area Environmental Characteristics in the NLSY79 restricted-use Geocode data:

• Population sizes
• Percent of population that is:
  • urban
  • black
  • female
  • under 5 years old
  • 65+ years old
• Birth/death/marriage/divorce rates
• Physician and hospital bed rates
• Crime rates
• Poverty level data
• Educational attainment levels 
• Median family and per capita income
• Recipients of and payments from:
  • AFDC
  • SSI
  • Social Security
• Labor force statistics:
  • total labor force
  • civilian labor force
  • number of females in the civilian labor force
  • civilians unemployed versus employed
  • percent employed in various industries
• Unemployment rate for labor market of residence

Geographic Residence: Detailed geographic mobility information was collected during the 1979-80, 1982, and from 2000 forward; data were gathered on the country/county/State and timing of up to five residential moves since January 1978 or since the last interview. Beginning in 2000 only significant geographical moves were recorded.

Neighborhood Quality: The neighborhood quality series (1992, and 1994-2000), is taken from the National Commission on Children Parent & Child Study, 1990 Parent Questionnaire. In this series of questions respondents rate how much of a neighborhood problem issues such as crime, lack of police protection, unsupervised children and joblessness are.

Other Geographic Variables: Users may obtain special permission to use zip code and Census tract data available at the BLS offices in Washington, DC.

Edited versus Unedited Versions of State/County of Residence: For some years (1979-82, 1988-89, 1991-92), two versions of the State and county of residence variables have been included in the "Geocode xxxx" files. The set occurring at the beginning of each file is the edited version, while the variables found near the end of the files for these years are unedited. If the variable has an actual source question number/name, it is the original from NORC. If the source question name says created, it is the edited/created version. Note that the unedited variables are sometimes combined into a single variable, with the State and county code appended to each other. These raw variables are preceded by the word "GEOCODE" in the variable title. The edited residence variables contain the corrections made for erroneous address information and are the ones from which the Geocode files themselves are constructed. Users should be aware that the edited version of these variables does not contain data for those respondents who are in the active military forces or who are living abroad or in a U.S. territory.  Codes of "-4" appearing in the unedited versions of the State or county variables (because foreign country and U.S. territory codes are placed in one field or the other) should not appear in the edited versions of these residence variables.

New Geocode Procedures for Assigning Residence Codes and Hand-Editing Discrepant Cases: During the 1988 hand-editing process, it became evident that the telephone numbers were very accurate, even in cases for which the address information contained discrepancies. Beginning in 1989, the area code and phone exchange were used to assign State and county of residence codes. The State assigned by the area code was then compared to the State assigned on the basis of zip code alone and the State contained in the original NORC respondent file. A "quality of match" variable was computed on the basis of how well these States match. For a more detailed discussion of these new assignment and matching procedures, refer to Appendix 10: Geocode Documentation in the Geocode Codebook Supplement. This process was used through the 1994 release.

The hand-editing procedure has also been streamlined. In 1989, the first year in which the phone assignment procedure was used, the residence codes assigned on the basis of the area code and exchange were compared to the raw residence variables received from NORC. Those with information that did not match were identified for individual examination. Ideally, the discrepancies requiring individual examination would be reduced to those cases which are "genuine movers" or which have zip codes covering multiple counties and would require some verification that the correct county was assigned based upon the phone information. The current process for identifying discrepancies and hand-editing is aimed more directly at achieving this objective. 

Beginning in 1990, the residence codes assigned based on phone information were compared to the 1989 CHRR-edited residence information to identify cases for individual examination. Because the previous year's edited variables incorporate the corrections that were made in the hand-editing process from earlier years, repeated editing of the same cases across years decreased. Through this process, the discrepancies in residential Geocode information were reduced. The number of cases requiring individual examination also decreased and was restricted more closely to the population of "genuine movers" and people with multiple-county zip codes and phone numbers that require verification of county of residence. 

The hand-editing process in previous years included not only these genuine movers and multi-county zip code dwellers, but also other cases for which elements of the address are simply in error or incompatible with each other. Some of these cases could potentially require editing for the same errors in more than one year, even if the respondent stayed in one location. Hand-editing procedures were further streamlined, and in some cases automated, to produce the 1992 data.

Beginning in 1996, a new procedure for verifying and assigning correct final Geocode information was instituted. This procedure is now performed using specialized address tracking Geocode software. The processes are described in Appendix 10. It is the belief of CHRR staff members not only that the current procedures are more efficient in identifying true discrepancies and streamlining the hand-editing process, but also that they result in more accurate and consistent assignment of State and county codes in general. 

Missing Values, New England Cases, and Mobility: Missing values in location of residence variables and metropolitan statistical area codes are associated with respondents who are in the active military forces or who are living abroad or in a U.S. territory. Users should be aware that, because the New England County Metropolitan Area (NECMA) codes are not comparable to metropolitan statistical areas from the remainder of the country, New England cases are eliminated from some of the procedures used to construct the Geocode files.

The review and hand-editing process has been periodically revised to improve the accuracy of the data and the efficiency of data production. The potential implications for effects on mobility rates between some years due to these changes have been noted in Appendix 10: Geocode Documentation. Users should read Appendix 10 carefully to gain a better understanding of the issues outlined above and their implications for specific research endeavors.

Comparison to Other NLS Cohorts: Data on the respondent's area of residence are available for all cohorts. Geographic residence information for those NLSY79 children who resided with their mother can be inferred from the residence data of their mothers. The NLSY97 main created variables indicate whether the respondent lives in an urban or rural area, whether the respondent lives in a Metropolitan Statistical Area, and in which Census region the respondent resides. More detailed information is available on the restricted-use Geocode data. Region of residence and geographic mobility of Original Cohort respondents are provided for most survey years. Geographic data for NLSY79 respondents fall into two categories: information on the main public file and more detailed information released as restricted-use Geocode data. These confidential files are available for use only at the BLS National Office in Washington, DC, and at Federal Statistical Research Data Centers (FSRDCs) on statistical research projects approved by BLS. Access to data is subject to the availability of space and resources. Information about applying to use the zip code and Census tract data is available on the BLS Restricted Data Access page.

Variables available within the NLSY79 provide information on the sex of each respondent, their children, and members of their household. Information on the sex of the respondent can be found in:

• a single 1979 variable, 'Sex of R' (R02148)
• a set of yearly interviewer remarks variables, 'Int Remarks - Sex of R' 

The 1979 'Sex of R' variable (R02148.) is derived from R01736., 'Sample Identification Code,' a variable which defines each respondent's membership in one of the subsamples that compose the NLSY79 (such as the "cross-sectional male, nonblack/non-Hispanic poor," "supplemental female black," and so forth). Subsample identification was based on information gathered during the 1978 household screening.

Comparison to Other NLS Cohorts: Sex for all biological children born to female members of the NLSY79 is available. Information on sex is also available for the NLSY97. Sex is implicit by membership in the Original Cohorts. For more precise details about the content of each survey, consult the appropriate cohort's User's Guide using the tabs above for more information.

Date of birth information was collected from each NLSY79 respondent during the 1979 and 1981 interviews:

• The variable 'Age of R,' gathered during the 1979-83 surveys, is the self-reported age of the respondent as of the interview date.
• The NLSY79 main data files also contain a yearly created variable, 'Age of R at Interview Date.' These created variables are constructed using the 1981 date of birth information coupled with the 1979 birth date for the 491 respondents not interviewed in 1981. 

Table 1 depicts age distribution of the NLSY79 for the 1979 survey year. Table 2 depicts age distribution of the NLSY79 for the 2018 survey year.

As the 1979 Youth cohort approached their fifties, questions were added about retirement preparation and expectations, starting with the 2006 survey year. 

Table 1 shows the retirement preparation/expectation variables and the survey years they have been asked. Variable question names begin with the "RETIRE_EXP" prefix.

In 2018, the retirement section was revamped and expanded so that respondents (many who were starting to retire) could provide more complete information about their retirement funds. Information on retirement income can be found in the Pension Benefits & Pension Plans section of this Users Guide.

Also in 2018, respondents were asked if their employer had ever offered an early retirement window, one with a special financial incentive like a cash bonus or improved pension benefits. 

¹ Only a random sample of 991 respondents were asked retirement expectations questions in 2006.

Prior to 2010, only limited information was collected on business ownership in the NLSY79. In 2010 (round 24), NLSY79 respondents who were current or former business owners were asked a lengthy series of questions about each business owned since age 18. The business ownership questions were also asked in subsequent survey years for those not interviewed in 2010. 

Respondents who reported having owned a business gave the year each business was established and how ownership was acquired: whether the respondent established the business themselves or with partners, received ownership as a gift, purchased ownership, inherited ownership, or received an ownership stake through marriage. Respondents answered questions about working for a related type of business prior to starting their business, the source of the money used to establish or acquire the business, the number of employees and the number of physical locations of the business, the legal form of the business (sole proprietorship, corporation, etc.) the sales or revenue in a typical year, and whether the business was family owned.

In addition, all NLSY79 respondents interviewed in round 24 (regardless of "own business" status) were asked several questions on family ownership of businesses, their own patent-seeking activities, and whether they consider themselves to be entrepreneurs. These questions were repeated in subsequent rounds for those who missed the round 24 interview.

To find these business ownership questions in NLS Investigator, use "BUSOWN" as the Question Name search criterion. These variables are listed as cross-round (XRND) variables. To determine whcih survey year the data were collected, use the created variable "BUSOWN_SOURCEYR."

The Employer History roster includes information on virtually all employers reported by NLSY79 respondents, with many of the employer characteristics reported for each employer included in a single record. These variables are classified as "XRND" variables, rather than being assigned to a single survey year. Data from each survey year are currently available. The variables will be updated as necessary as revisions are made and with each progressive round.

Structure

In earlier years, the linking process required to build a record of various commonly used employer-specific characteristics that have been reported in different survey years has involved a rather complex process. Researchers would need to use variables indicating the employer number in the previous survey year and establish the link through each preceding year individually. Appendix 9: Linking Employers Through Survey Years details this process.

By contrast, the Employer History roster is designed to help alleviate that more involved process of employer linking for many of the most commonly used employer characteristics. The Employer History data is constructed in a roster structure, consisting of one record for each of the up to 65 jobs (so up to 65 records). Many employer characteristics have been compiled into each employer's record. The record for each employer will include each of the variables listed in the table below. For instance, the record for employer #1 will contain EMPLOYERS_ALL_CPSJOB_[YEAR].01, EMPLOYERS_ALL_UNION_[YEAR].01, EMPLOYERS_ALL_IND_[YEAR].01, EMPLOYERS_ALL_OCC_[YEAR].01, etc. for each survey year that employer #1 was reported.

Data Notes

Employer information for additional employers (jobs 6-10) in some of the older survey years may not have been included in the roster. These jobs were often included on separate data tapes, the original data of which has been difficult to recover. Should any of these data on additional employers be recovered in the future, that data will be added to the Employer History roster accordingly and users notified of these additions. These employers comprise a very small proportion of those ever reported for a very small number of respondents.

Locating Employer History variables

The Employer History items can be easily located within the NLSY79 dataset on NLS Investigator by using one of the following search criteria:

• Question Name (enter search term) index, "starts with", enter "EMPLOYERS_ALL" search term
• Area of Interest (pick from list) index, "equals", choose areas of interest beginning with "EMPLOYERS_ALL"
• Reference Number (enter search term), "starts with", enter "E"

Table 1 lists the contents of the Employer History roster. The variables are listed under the Areas of Interest currently assigned. The "variable names" column contains the qnames for each of the variables. Currently there are up to 65 jobs for each respondent included on the roster. This means that at least one respondent has reported 65 jobs over the course of the NLSY79's 27 rounds. Most respondents of course will have a much smaller number of jobs reported since 1979.

Table 1: Employer History Roster Contents by Area of Interest

Beginning with the release of the 2000 data, the Work History file is incorporated into the main NLSY79 data set. Variables previously located on the separate Work History file can be identified by searching for areas of interest beginning with "Work History." In addition, the reference numbers for work history variables begin with "W." Key work history variables are described below.

Weekly Arrays: Week-by-week records of the respondent's labor force status and associated job(s), if employed, and the total number of hours worked each week at any job, if employed, are available. This information is contained in the three arrays described above.

Although data on only up to five jobs are released, data are collected on all jobs. Data for the extra jobs are used to construct summary KEY variables by the work history programs. The number of jobs has exceeded ten for one case in 1991 and 1992, two cases in 1998, and one case in 2000.

Many researchers focus on data for the CPS job. Because the CPS was Job #1 only in select years, researchers should see the "Important Information" box in the Labor Force Status section for an elaboration of this concept.

Employment Gaps: Gaps within tenure with a specific employer are reported in association with that employer. They occur between the start and stop dates given for an employer. The respondent does not consider himself/herself completely disassociated from the relevant employer during these periods, although he or she was not actively working for that employer. Specific variables for each gap include start and stop dates; the reason that the respondent was not working; the number of weeks that a respondent was unemployed (looking for work or on layoff) or out of the labor force (OLF or not looking for work); and, for those who were OLF at some time during a gap, the reason they were not looking for work. See the Work Experience section for a discussion of gaps with respect to job tenure.

Gaps between employers are gaps in a respondent's employment during which he or she was not associated with any employer. The specific variables collected with respect to "within job gaps" (see the discussion in the Work Experience section on tenure with a specific employer) are also collected with respect to gaps between employers, with the exception of the reason that the respondent was not working during the gap.

The information collected on reasons for employment gaps allows specific dates to be fixed for unemployed or OLF status only if a respondent was unemployed or OLF for the entire period of the gap. If the respondent was unemployed for part of the gap and OLF for the other part, the number of weeks unemployed and OLF is recorded, but the specific dates of periods for which the respondent was actively looking for work/on layoff and not looking for work are not collected. This prevents the Work History program from assigning specific week numbers to these statuses in the event of such a "split gap." Instead, the number of weeks reported as unemployed is assigned to the middle of the total gap period, with the remainder of weeks at the beginning and end of the gap period being assigned an OLF status. Users examining the week-by-week status array containing labor force statuses should be aware that "split gaps" will appear as a series of "5" codes, followed by a series of "4" codes, followed by another series of "5" codes (5 5 5 5 5 .... 4 4 4 4 4 .... 5 5 5 5 5). Although the start and stop dates for the whole gap will be those actually reported by the respondent, the assignment of the unemployed and OLF statuses will not represent actual dates reported by the respondent. They represent only the number of weeks that a respondent reported having held each status, with the unemployed status being arbitrarily assigned to the middle portion of the gap.

Summary Labor Force Related Variables: Variables are constructed summarizing different aspects of a respondent's labor force activity, including total number of hours worked, weeks worked, weeks unemployed, weeks out of the labor force, and weeks in active military service. There are two sets of these variables, referring to each of two time periods--the period since the last interview and the past calendar year (see the Labor Force Status section). Variables are also created indicating the number of weeks since the previous interview and the percent of weeks for which a definite status cannot be determined in constructing the summary variables discussed above. See the Work Experience section for further notes on these variables.

Tracing Employers Back Through Contiguous Survey Years: Of particular interest to many researchers have been the PREV_EMP# and TENURE variables associated with each employer. The PREV_EMP# allows a respondent's association with a given employer to be traced back through contiguous survey years. Using PREV_EMP# and the appropriate start and stop dates, a TENURE variable is constructed for each job reported, which depicts total weeks of tenure with each employer across contiguous survey years. Examine the work history documentation in Appendix 18 to determine if any such time-saving variable constructions exist. 

Creation of the Work History Data

The work history is a complete retrospective up to and including the respondent's most recent date of interview. The questions in these survey sections are constructed to collect a complete history for each respondent, regardless of period of noninterview. For example, a respondent previously interviewed in 1984 and not interviewed again until 1989 will have a complete labor force history as of the 1989 interview, as information for the intervening period will be recovered in the 1989 interview. The Work Experience section contains a discussion of possible discrepancies or inconsistencies in these data. Researchers should be aware that, although such possibilities exist, they have not appeared to be a major factor in the quality or completeness of the work history record.

Be aware that for respondents with simultaneous active military status and civilian employment status, civilian labor force activity will take precedence over military status. For the purposes of constructing the week-by-week status array, the civilian job number will replace the military status code for weeks in which both statuses occur. The order of precedence for various labor force status codes is detailed in the work history documentation (see the discussion of the work history PL/I program in Appendix 18 of the NLSY79 Codebook Supplement); see also the Work Experience section.

For purposes of constructing the status array and computing the summary labor force activity variables, the work history programs require that specific week numbers be assigned on the basis of the job-specific start and stop dates. In the event that missing data occur in the job-specific start and stop dates, the programs take one of two actions. 

1. If only the day in a given date is missing, the program assigns the number "15," placing these dates in the middle of the month. This allows an approximate week number to be assigned. The possibility still exists, however, that a negative job/gap duration will result because the day is arbitrarily fixed. For example, a start date of 10/-2/90, which indicates a missing day, and a stop date of 10/6/90 would be read by the work history program as 10/15/90 and 10/6/90 respectively. Therefore, when the week numbers are assigned, the arbitrary assignment of "15" as the start day would give an erroneous impression that a job started after it stopped. The status array and computed summary variables will reflect the invalid data in the week numbers.
2. Dates missing a month or year cannot be estimated by the work history program and therefore have invalid missing codes for the week numbers. The status array and other computed variables cannot be calculated for activity within periods for which either or both of the dates have such missing information. These will also register invalidly missing information for any period in which specific dates and week numbers cannot be determined.

Comparison to Other NLS Cohorts: The NLSY97 Event History file contains created variables summarizing the month and year in which major life events occurred for each respondent, along with all main file data. Variables cover topics such as marital status, enrollment, employment status, and program participation. The NLSY97 Event History file presents employment status information in a format similar to the NLSY79 employment information, using a continuous week timeline. Although the NLS has collected information on labor force behavior since its inception, only partial work histories for respondents in the Original Cohorts can be constructed for certain survey years. The degree of completeness of the work history data varies by cohort and survey year. For more precise details about the content of each survey, consult the appropriate cohort's User's Guide using the tabs above for more information.

Data on respondents' usual earnings (inclusive of tips, overtime, and bonuses but before deductions) have been collected during every survey year for each employer for whom the respondent worked since the last interview date. The amount of earnings, reported in dollars and cents, is coupled with information on the applicable unit of time, such as per day, per hour, per week, or per year. Since 1988, those respondents reporting any unit of time other than "per hour" have been asked a follow-up question on whether they were paid by the hour on that job; if so, an hourly wage rate was collected.

The raw earnings data, collected in the Employer Supplements during each round of the survey and in Section 10 of the 1979 questionnaire, can be found in the variable series 'Rate of Pay Job #1-5' and 'Time Unit of Rate of Pay Job #1-5.' Two sets of variables provide information based on the combined earnings and time unit data. The first set, 'Hourly Rate of Pay Job #1-5,' provides the hourly wage rate for each job as reported. The actual responses of those respondents who report wages with an hourly time unit in the initial earnings question appear in this variable. For those reporting a time unit other than "per hour" or "other" in the initial earnings question, an hourly rate of pay has been calculated. 

A second set of variables based on responses to the initial set of wage/time unit questions, entitled 'Hourly Rate of Pay Current/Most Recent Job,' identifies the hourly earnings for the job identified as the CPS job, that is, the job that the respondent held most recently. Hourly wage rates for those respondents who reported a time unit other than "per hour" can be found in the 1988-93 variables series, 'Paid by the Hour (Time Unit Other than Hourly Previously Reported) Job #1-5' and 'Hourly Rate of Pay (Rate Other than Hourly Previously Reported) Job #1-5.' Table 1 depicts the core set of rate of pay variables present on the NLSY79 combined Main/Work History Data.

Follow-up questions starting in 1986 asked those respondents whose earnings had changed for wage rate and time unit information at the time they first started working for a new employer. In 1986 and 1987, those who were not working for the employer at the interview date were also asked for wage information at the time they left that employer. These data can be found in the following variables: 'Wages Changed Since First Began Working Job #1-5,' 'Rate of Pay When 1st Began Working at Job #1-5,' 'Time Unit of Rate of Pay When 1st Began Working at Job #1-5,' 'Rate of Pay When Last Worked at Job #1-5,' and 'Time Unit of Rate of Pay When Last Worked at Job #1-5.'