Although the NLS has collected information on labor force behavior since its inception, only partial work histories for respondents in the Older Men cohorts can be constructed for certain survey years. The degree of completeness of the work history data varies by cohort and survey year.
For those wishing to measure labor force attachment over time, three approaches are available. One can examine: (1) the amount of time in weeks that a respondent spent working, unemployed (looking for work), or out of the labor force; (2) the start and stop dates of each job a respondent has held (a continuous job history); or (3) the start and stop dates associated with each employer for whom a respondent worked (a continuous employer history).
In general, summary weeks data (information on the number of weeks working, unemployed, and out of the labor force) were collected during each interview for either the previous 12 months or the previous calendar year. The term "summary weeks data" refers to the respondent's answers (in weeks) to the following types of questions: "During the past 12 months, in how many different weeks did you do any work at all?" Respondents who worked 52 weeks were asked, "Did you lose any full weeks of work during the past 12 months because you were on layoff from a job or lost a job?" Respondents who worked less than 52 weeks were asked, "In any of the remaining weeks, were you looking for work or on layoff from a job?" Those answering "yes" were asked to report the number weeks. Respondents who did not work during the past 12 months were asked if they had spent any time looking for work or on layoff and if they had, how many weeks. While placement and wording of the individual questions have varied, this core set of summary questions is always present in each interview.
Unfortunately, such data collection consistency did not occur in obtaining information to track all job and/or all employer changes. The gaps in information collected on weeks worked are minor compared to the gaps in information on jobs held and employment spells.
There are three different ways to construct a summary measure for number of weeks worked, seeking work, or out of the labor force. Users can examine the start and stop dates associated with each job, especially in the personal interview years, when the questionnaire included a detailed work history in a column format. (These variables can be found in NLS Investigator under the keyword "Most_Recent_Job.") When the information about start and stop dates is combined, a fairly complete picture of total number of weeks in the labor force can be pieced together. This is the procedure that has been used at CHRR to create the *KEY* weeks variables. Users attempting to create number of weeks worked themselves instead of using the created *KEY* variables need to pay close attention to the skip patterns followed in the early survey years. Many check items sent respondents to different parts of the questionnaire to answer questions worded specifically for their particular situations. When constructing number of weeks worked, users should pay particular attention to the dates in the detailed work history section. During the early survey years, the Census Bureau truncated the date the respondent started the job to the preceding interview date if it started before then, so the actual start date may not be available; in the later years, when an interviewer inadvertently gathered information before the date of the last interview, this information was sometimes left on the data file instead of being blanked out and eliminated.
Two alternatives to this time-consuming procedure of piecing the record together from start and stop dates include: (1) use of information from the summary weeks questions present in the questionnaire for all years or (2) a combination of data from the *KEY* summary weeks variables for those years in which they were constructed and information from the summary weeks questions for those years in which no *KEY* variable is available. The *KEY* variables (those variable with titles of '# of Weeks_Worked [reference period] *KEY*,' '# of Weeks_Unemployed [reference period] *KEY*,' and '# of Weeks_OLF [reference period] *KEY*') were created for all survey years in which respondents were personally interviewed, except for the 1990 Older Men resurvey. Care should be taken to check that the number of cases on the summary weeks variables is reasonably close to the number of respondents interviewed (since all respondents should have a value on these variables). If this is not the case, the user needs to make sure that the desired information is not present in another part of the questionnaire or to adjust for the fact that in some years respondents who had not worked since the last interview are assigned to "NA" or missing instead of being assigned a "zero" for zero weeks of works, as one would expect.
Gaps in the reference periods for the summary week variables occur in the early 1970s when the project phased in an alternating personal and telephone interview pattern. The regularly fielded personal interviews conducted during the early survey years gave way to a 2-2-1 interview pattern (i.e., two telephone interviews occurring two years apart followed by a personal interview at the end of the five-year period). The intent of the telephone interview was to obtain a brief update of information on each respondent and to maintain sufficient contact such that the lengthier personal interview could be completed. Due to the fact that the reference period for the summary weeks questions within a telephone interview was the previous 12 months and that no interview was conducted the year before each telephone survey, gaps in the summary weeks records of Older Men respondents occurred. However, questions were added to the Older Men personal interview instruments that gathered information on weeks not worked over a five-year period, including the two missing years. By using simple subtraction, the total number of weeks worked over the five year period can be calculated.
The discussion below reviews by the types of summary weeks information that are available from the questionnaire. Included is information on changes in the reference periods for which these data were collected. The weeks worked accounting is not completely accurate due to the slight over- or under-counting of weeks that occurs when a respondent is not interviewed exactly one year from the date of the last interview. If the respondent accurately answers the question on the number of weeks worked in the last (or past) 12 months and it had been 13 months since the last interview, the summary weeks variables would miss four weeks of employment status information. Although Census was asked in the early years to interview each respondent as close as possible to the date of the previous interview, the actual dates of interview can and should be checked.
A nearly complete work history for weeks worked and a complete listing of the most important or longest held jobs are available for respondents in the Older Men cohort.
1966 Survey. During the initial 1966 survey, each respondent was asked detailed questions regarding the following four jobs: (1) his current job or the last job he had held since 1961, (2) the job he had held before his current job or before his last job if it started after 1961, (3) the longest job of all the jobs he had ever had, and (4) the first job he had held for at least a month after stopping school full-time. By looking at the start and stop dates for these jobs, it is possible to obtain a global measure of weeks worked up to 1961 and a measure of weeks worked between 1961 and the date of the 1966 interview. Summary weeks questions, e.g., the number of weeks working, weeks unemployed, and weeks out of the labor force, were asked of the respondent for the calendar year 1965.
1967 Survey. The 1967 questionnaire included questions on the current or last job for those respondents who had worked at all since June 15, 1966. Information was also gathered on one intervening job. If the respondent had held more than one such job, information was gathered on the job with the longest tenure. Respondents were also asked the summary weeks questions; however, the reference period on these questions was the last 12 months, not the previous calendar year as it was in 1966.
1968 Survey. The 1968 mail survey elicited information on the respondent's current job or his last job since June 1, 1967. The questionnaire also asked the respondent to report the total number of intervening jobs in the past 12 months and to describe the characteristics of the longest intervening job. Summary weeks questions refer to the last 12-month period.
1969 Survey. In the 1969 survey, respondents were asked about their current job or their last job since June 1, 1968. If the respondent had changed jobs since the last interview, he was again asked for the total number of intervening jobs and for details about the job held the for the longest time. The summary weeks questions asked about the last 12-month period.
1971 Survey. The 1971 interview first collected information about the respondent's current job and a dual job, if applicable. This survey then used a column format to collect information about all jobs held since the date of the last interview. The summary weeks questions also referred to the date of the previous interview. This means that, except for those respondents who were not interviewed in all years, a reasonably accurate number of weeks worked between 1965 and 1971 can be obtained.
1973 and 1975 Surveys. Gaps in the employment record start with the 1973 telephone interview. In this shorter survey, respondents were asked questions only about their current job or the last job held since August 1971. The summary weeks questions were asked about the previous 12 months. The 1975 telephone interview followed a similar pattern, collecting information about the respondent's current job or his last job since August 1973. The summary weeks questions again refer to the previous 12-month period.
1976 Survey. In the 1976 personal interview, any respondent who had worked since August 1971 was asked for information on his current or last job, the job he held before his current or last job, and the job he had held for the longest time since 1971. There are two different sets of summary weeks questions. The usual set of summary week questions was asked for the previous 12-month period; another set collected information on weeks not working for the previous five years. These variables, '# of Weeks Not Working, 71-76,' '# of Weeks Unemployed, 71-76,' and '# of Weeks OLF, 71-76,' can be used to patch the gaps left by the telephone interviews.
1978 and 1980 Surveys. The 1978 telephone interview asked the respondent about his current job or the last job he had held since the 1976 interview date (or since August 15, 1976, if the respondent was not interviewed in 1976). The summary weeks questions asked about the last 12 months. The 1980 telephone interview repeated the 1978 pattern.
1981 Survey. The 1981 personal interview was similar to the 1976 survey. Respondents provided information about their current or last job, the job they had held for the longest time in the past 12 months, and the job they had held for the longest time since August 1976. As in the 1976 survey, there were two sets of summary weeks questions, one series asking about the previous 12 months and the second series referring to the period since August 1976.
1983 Survey. The 1983 telephone interview mainly repeated the 1978 pattern; respondents provided information about their current job and the longest job held since the 1981 interview (or since August 15, 1981, if not interviewed in 1981). Respondents then answered summary weeks questions referring to the previous 12 months. However, the first set of summary weeks questions was followed by a second series that asked about the 12 months before that, so that the 2-year period between the 1981 and 1983 surveys was fully covered (depending on exact interview dates).
1990 Survey. The 1990 reinterview survey included two questionnaires. The questionnaire addressed to living Older Men respondents (or their proxies) asked all respondents about their current or last job. Respondents who were institutionalized or who had not worked at all since their last interview were skipped past the remaining work experience questions. Those who remained in the eligible universe provided information about the job held the longest since their last interview, if it was different from the current or last job, and about the number of weeks worked each year from 1983 to 1989. Respondents who had not worked 52 weeks in 1989 were asked if they had been looking for work or on layoff during weeks not working.
The 1990 widow questionnaire collected more limited information about the sample person's work experiences. The widow (or her proxy) first reported the date the respondent stopped working at the job he held at his previous interview date. She then answered questions about the longest job held by the respondent between his previous interview and his death and about the last job the respondent held before his death.
For those respondents still alive in 1990 (and surveyed in every personal interview year), summary weeks information on weeks working, weeks unemployed, and weeks out of the labor force is available for the years 1966 to 1983 and for 1989. Information on weeks worked is also available for the period 1983 to 1988. For deceased respondents who consistently participated in the survey, summary weeks information is available for 1966 through 1983. Employment start and stop dates collected about deceased respondents during in the widow interview can be used to provide some information about the number of weeks worked, although sample persons who held more than three jobs between 1983 and their death are missing information about some jobs.
The tables below are presented to provide the researcher with information on sample sizes by race and interview year for weeks worked and number of employers. Due to the restructuring of the 1990 interview, tables for the Older Men cover the years 1966-83. The labor force attachment of Older Men interviewed in 1990 is described in Parnes et al. (1992, 1994).
Table OM1, "Number of Weeks Worked All Survey Years," provides information on the average number of weeks worked by respondents interviewed in all survey years. This summarizes all information available on number of weeks worked. Table OM2, "Number of Weeks Worked/Year by # of Survey Years Reported Work," presents information on the average number of weeks worked by number of years that the respondent was interviewed. Table OM3, "Number of Weeks Worked by Survey Year," depicts the number of weeks worked for each respondent interviewed in that survey year, including both the mean and number of cases for those who report work and those who do not report any weeks worked. Table OM4, "Number of Employers by Survey Year," presents information on the numbers of employers reported during each survey year.
A number of decisions were made during the construction of these tables in an attempt to make the information comparable across cohorts. The tables are not weighted and are not intended to be used to make inferences about populations. The universe for the first two sets of tables is all respondents who were interviewed in all years. Years in which the *KEY* or summary week variables were found to have an upper range greater than 52 were truncated back to 52. In those years that a *KEY* variable covers a two year period, the total number of weeks was divided by two. The weeks tables do not take into account whether or not the respondent was in the labor force; if a respondent was interviewed and did not report any weeks worked, he was assigned a "zero" even if, for example, he was permanently handicapped and would not have been in the labor force under normal conditions. The number of respondents in the "NOT WORKING" categories in the third and fourth set of tables are similar although not identical. There was no attempt to eliminate respondents who did not have information available for both weeks and employers. The last set of tables presents information on the number of employers reported each survey year; however, the reference period varies between and across cohorts. "Survey year" could refer to the last twelve months, or to a period since the last interview that was one, two, three, or more years ago. Examining information on the total number of employers across time is difficult and time-consuming. Although it is possible to find information for most detailed work history years on the same and different employers within the survey period, the main linkage across years is the one for the current employer in the "CPS" section. (The CPS section refers to the series of employment questions that replicated the questions asked in the monthly Current Population Survey (CPS) of American households conducted by the U.S. Census Bureau for the U.S. Department of Labor). In other words, it is not possible in the early survey years to know, for example, that the intervening employer in the second column of the detailed work history section is the same employer as that entered two years later in the third column of the work history without making a number of assumptions based on matching of the job and/or employer characteristics. In later survey years, it is possible to link an employer in a work history column to the employer at the time of the last interview. However, use of this extra information was beyond the scope of these tabular presentations.
Table OM1. Number of Weeks Worked All Survey Years (Unweighted): Older Men
Number of Cases
Table OM2. Number of Weeks Worked/Year by # of Survey Years Reported Work (Unweighted): Older Men
# Years Reported Work
# of Cases
# of Cases
# of Cases
Table OM3. Number of Weeks Worked by Survey Year (Unweighted): Older Men
Average Weeks Worked
Respondents Not Working
Table OM4. Number of Employers by Survey Year (Unweighted): Older Men
Average # of Employers
Respondents Not Working
Note: Questions about number of employers missing in some years.
Parnes, Herbert S., et al. The NLS Older Male Sample Revisited: A Unique Data Base for Gerontological Research. Columbus, OH: CHRR, The Ohio State University, 1992.
Parnes, Herbert S. and Sommers, David G. "Shunning Retirement: Work Experience of Men in Their Seventies and Early Eighties." Journal of Gerontology 49, 3 (1994): S117-S124.