26 Monthly Labor Review June 1997

Measuring Job Security

I

t has been argued that in order to control costs,

 firms are increasingly seeking more flexibil-

 ity in their use of labor. This argument has

been widely made in both the academic and the

popular press.1 Employers have sought this additional flexibility within their own work forces,

as well as from sources outside their organizations. Internally, they have hired workers on a

temporary basis; externally, they have obtained

labor through temporary help agencies or by contracting with firms or individuals to provide specific services. Anecdotal evidence of the trend

toward more flexible employment arrangements

is fairly extensive; measuring the extent of such

employment in the labor force as a whole, however, has been more problematic.

The Bureau of Labor Statistics has collected

some information that can be used to analyze job

security in the United States. In periodic supplements to the Current Population Survey (CPS),

individuals are asked about job tenure—time

spent with their current employer. In February

1995, the Bureau conducted the first supplement

to the CPS designed to obtain more information

on another aspect of this issue: contingent and

alternative employment arrangements. Contingent jobs, as defined in the supplement, are structured to last only a limited period; alternative

employment arrangements include those made

through intermediaries and those without standard work schedules.2 In this article, data from

recent CPS supplements are used to examine the

quality and the nature of variables that are utilized to measure job security.3

Job security is difficult to measure directly,

but data on job tenure and contingent employment

provide a means of examining the issue

Measuring job security Measuring job security

Thomas Nardone,

Jonathan Veum,

and

Julie Yates

Thomas Nardone,

Jonathan Veum, and

Julie Yates are economists in the Office of

Employment and

Unemployment

Statistics, Bureau of

Labor Statistics.

Time spent with an employer, or job tenure, is a

commonly used variable in studies of the labor

market that focus on topics such as labor supply,

job search, and job turnover. A number of recent

studies have examined data on job duration from

the CPS in order to provide direct empirical evidence of declining job stability in the U.S.

economy.4 Although the results are not completely consistent, these studies generally find

little, if any, decline in job stability in the last

two decades. While certain subgroups of the

population, such as those with less education, experienced less job security than in the past, for

the most part these analyses indicate that there

was no systemic change in the duration of jobs

over time.

One issue that arises when examining job

duration is the quality of the job tenure data in

the CPS. Information on how long individuals have

worked continuously for their current employer

is available in periodic CPS supplements. Yet this

information often is viewed as being relatively

crude, given that durations are measured in years

and the frequency distributions tend to exhibit

spikes at years that are multiples of 5. Hence,

the information may contain substantial recall or

rounding errors.

Evidence from other U.S. data sources also

indicates that data on job tenure are often problematic. In particular, James N. Brown and

Audrey Light found that in the Panel Study of

Income Dynamics, which interviews the same

Measuring Job Security

Measuring job tenure
 Monthly Labor Review June 1997 27

people over time, responses to tenure questions were often

inconsistent with calendar time.5 For example, in a particular

year an individual might claim to have been working for an

employer for 3 years, but in the subsequent year the same person would claim to have been working with the same employer

for 6 years. Inconsistent responses such as these suggest that

data on tenure are often unreliable, even when collected longitudinally.

Another longitudinal data source, the National Longitudinal Survey of Youth (NLSY), collects data in a way so as to

minimize recall problems and rounding errors. These data describe a sample of young men and women who were between

the ages of 14 and 22 in 1979 and have been interviewed regularly since then. The NLSY collects data in an event history format, in which dates are collected for the beginning and ending

of important events. In the case of work, the starting date for a

job is recorded, and if a person stops work for that employer,

the ending date also is recorded. The times in between jobs

are then confirmed as gaps for further investigation. For multiple jobholders, information is collected for each job, with

beginning and ending dates. Periods of nonwork within a job,

such as periods when an employee is on layoff, ill, pregnant,

and so forth, are also recorded. By recording the dates of all

jobs and all periods of nonwork, the survey provides a nearly

complete and continuous employment history for each individual in the sample.

Information on other major events also is collected in this

manner. The months spent in school are identified, as is the

timing of training programs. Also collected are dates of changes

in marital status and the birth of children. By linking the dates

of all these events, survey designers believe that individuals

will be more able to provide accurate responses to the questions relating to the times of the events.

While collecting data in this event history format is still

subject to recall and other errors, the methodology may decrease the likelihood of recall error with respect to time spent

working, because respondents can link the dates of events such

as the birth of children and changes in marital status to changes

in employment. Also, the longitudinal nature of the data allows for employment at a particular job to be linked across

years, which could substantially lower the extent of recall problems often associated with job tenure data.

In addition, the event history format of the NLSY allows for

a number of techniques that may improve the quality of the

data. For example, interviewers are provided information about

employers’ names from the previous interview and use these

to see whether workers still have the same employer. Calendars in the form of a time line are placed in front of respondents so that they may better visualize their periods of work and

nonwork. Research on retrospective reports of individual events

indicates that intervention techniques which help respondents

place events into a personal time line substantially improve

the respondents’ recall.6

In the next section, recent job tenure data from the NLSY are

compared with tenure data from a similar cohort of individuals from the CPS.

7 This comparison provides evidence as to

how the data differ by the two collection techniques. Presumably, due to the multiple techniques incorporated into the NLSY

that are used to enhance the quality of the data, the data provide a relatively accurate portrayal of individual work histories and should be a good yardstick to examine the quality of

similar CPS data. It is important to mention that the comparison

is made using a relatively young age group, rather than the full

age distribution. Consequently, the job durations for this age

group are generally shorter and less dispersed than those for

all workers.

The tenure distributions

Table 1 provides information on the distribution of job tenure

among 28- to 36-year-old workers in 1993 using the CPS and

the NLSY.

8 The percentiles can be computed directly from the

NLSY data, because these data are available in weeks, which

provides for a fairly continuous distribution. In contrast, calculating percentiles from the CPS data is more difficult, as the

information is available only in years. The cumulative distribution function for integer data is a step function, and movement along a step will not change the percentile until another

step is reached. One solution to this problem is to compute

“interpolated” percentiles, which assumes that job tenure is

uniformly distributed within each interval. This method essentially involves taking a weighted average of the integer in

which the percentile falls and the previous integer.9

For the most part, the figures in table 1 indicate that the two

tenure distributions are surprisingly similar. For example, median tenure using the CPS is 3.34, while for the NLSY, it is 3.46.

One might expect that the upper tails of the distributions would

show the greatest disparities, because recall problems are likely

greater for CPS respondents with longer job durations. Yet at

the 90th percentile, there is little difference between the two

distributions, with CPS job tenure registering 11.22 and that of

the NLSY 11.13.

Also shown in the table are tenure data for subgroups based

on gender, race or ethnicity, and education. For most of the

subgroups, the two tenure distributions are not as similar as

that for the full sample, but the differences are usually relatively minor. The largest disparities appear to be among blacks

and high school dropouts at the 90th percentile, in which the

CPS tenure data are about 1 year higher than those of the NLSY.

Hence, there is some evidence that the CPS data may be problematic at longer job durations among these groups.

Are the differences in the two tenure distributions sensitive

to business cycle fluctuations? Job tenure may vary with

changes in the business cycle due to corresponding changes in

Measuring Job Security
28 Monthly Labor Review June 1997

Measuring Job Security

the composition of the workers. For instance, an economic

expansion may lead to more hiring and to a larger sample of

relatively inexperienced workers or workers with less tenure.

Conversely, an economic contraction may result in fewer inexperienced workers being employed, and the resulting group

of workers may therefore have more tenure. Because recall

may be more problematic for those with more tenure, particularly when the CPS method of collecting data is used, the differences in CPS and NLSY tenure data may be more severe during

economic contractions.

In order to examine data at two points in the business cycle,

table 2 provides information on median job tenure in 1988

and 1993. (In 1988, the national unemployment rate was 5.5

percent, whereas in 1993, it was 6.8 percent.) To examine workers at comparable ages in both years, it is necessary to restrict

the NLSY and CPS samples to 28- to 31-year-old workers in each

Table 1. Distribution of years of tenure among 28- to 36-year-old workers, Current Population Survey (CPS) and National

Longitudinal Longitudinal Longitudinal Longitudinal Longitudinal Survey of Youth (NLSY), 1993

Percentile Percentile Percentile Percentile Percentile

10th 25th Median 75th 90th

 Total

CPS .................................................................................. 0.04 1.04 3.34 7.00 11.22

NLSY ................................................................................ .37 1.13 3.46 7.03 11.13

 Sex

Male:

CPS .................................................................................. .04 1.19 4.00 7.52 11.28

NLSY ................................................................................ .35 1.13 3.62 7.25 11.42

Female:

 CPS ................................................................................... .04 .97 2.91 6.47 11.17

 NLSY ................................................................................. .38 1.13 3.19 6.62 10.83

 Race or ethnicity

White:

CPS .................................................................................. .04 1.10 3.60 7.22 11.31

NLSY ................................................................................ .37 1.15 3.54 7.15 11.27

Black:

CPS .................................................................................. .04 .92 2.91 6.72 11.37

NLSY ................................................................................ .29 .92 3.08 6.44 10.15

Hispanic:

CPS .................................................................................. .04 1.00 2.42 5.78 10.01

NLSY ................................................................................ .35 1.19 3.17 6.19 10.57

 Education

High school dropout:

CPS ................................................................................... .03 .85 2.54 4.87 9.67

NLSY ................................................................................. .17 .65 1.92 5.56 8.87

High school graduate:

CPS ................................................................................... .04 1.04 3.73 7.97 12.15

NLSY ................................................................................. .29 1.08 3.46 7.58 12.62

Some college:

CPS ................................................................................... .04 1.14 3.67 7.61 11.74

NLSY ................................................................................. .44 1.19 3.48 6.94 10.92

College graduate:

CPS .................................................................................. .04 1.08 3.03 6.12 9.41

NLSY ................................................................................ .60 1.52 3.77 6.88 9.88

NOTE: The race/ethnicity categories are mutually exclusive and exhaustive. The “Hispanic” category includes white and black Hispanics. The “black” category

includes only non-Hispanic blacks. The “white” category includes all nonblacks and non-Hispanics.

Characteristic and survey
 Monthly Labor Review June 1997 29

year.10 The data indicate that overall job tenure is somewhat lower

during economic expansions, as expected. In particular, median

job tenure, according to the CPS, was 2.50 in 1988 and 2.87 in

1993. Still, in both years, the differences in median tenure between the two surveys are fairly small. The differences for

some of the subgroups are often larger than that for the full

sample, but the sample sizes in many of these subgroups are

relatively small.11 Thus, the data in table 2 appear to reinforce the finding that there are no large differences in the two

tenure distributions and that whatever differences there are

are not particularly sensitive to changes in the business cycle.

In sum, then, despite the differences in data collection methods between the CPS and NLSY, the differences in the job tenure

distributions are very small. Some evidence does suggest that,

among certain subgroups of the population, the CPS may overstate job tenure at longer durations or when recall is more

problematic. Overall, however, the CPS data appear to provide

an adequate approximation of the tenure distribution among

young workers.

The results suggest that the extent to which information on

tenure needs to be “precise” depends upon the type of analysis undertaken. Certainly, for some studies—particularly those

dealing with job turnover—job tenure data measured in months

or weeks, as are available in the NLSY, are the most desirable.

Yet many of the recent studies based on CPS tenure data that

deal with job stability generally compare trends in relatively

simple statistical variables. Consequently, in these recent

analyses, the CPS tenure data should provide a satisfactory description of the tenure distribution and of changes in job durations over time.

Measuring contingent employment

The first special CPS supplemental survey to produce estimates

of the number of workers in contingent jobs—that is, jobs

which are structured to last only a limited period of time—

was completed in February 1995. Prior to this survey, the term

“contingent work” had been used to refer to a variety of work

arrangements, including part-time work, self-employment, employment in the business services industry, and, in fact, almost any work arrangement that might be considered to differ

from the commonly perceived norm of a full-time wage and

salary job.

Initial results from the February 1995 survey show that, at

that time, between 2.7 million and 6.0 million workers—a

range of 2.2 percent to 4.9 percent of total employment—

were in contingent jobs. (See table 3.) This range spans three

alternative estimates that were developed to assess the impact of different assumptions about the factors that constitute

contingent employment. The narrowest estimate includes only

wage and salary workers who had been in their jobs for 1 year

or less and expected the jobs to last for an additional year or

less. Self-employed workers, both incorporated and unincorporated, as well as independent contractors, are excluded from

this estimate, the rationale being that, by definition, people

who work for themselves have ongoing employment arrangements, although they may face financial risks. Also, workers

employed by temporary help agencies or contract companies

are not considered contingent if they expect to be able to stay

with the firms for more than 1 year or have been with the firms

for that amount of time, even if the places to which they are

Table 2. Median years of tenure among 28- to 31-year-olds, Current Population Survey (CPS) and National Longitudinal Survey

 of Youth (NLSY), 1988 and 1993

1988 1993

CPS NLSY CPS NLSY

Total .................................................................... 2.50 2.52 2.87 3.00

 Sex

Male ........................................................................... 2.65 2.69 3.38 3.04

Female ....................................................................... 2.37 2.25 2.59 2.97

 Race or ethnicity

White .......................................................................... 2.65 2.62 3.16 3.08

Black .......................................................................... 2.31 2.13 2.31 2.65

Hispanic ..................................................................... 1.66 2.29 1.75 2.73

Education Education Education Education Education

High school dropout ................................................... 1.53 1.58 1.93 1.67

High school graduate ................................................. 2.39 2.83 3.21 2.93

Some college ............................................................. 3.03 2.36 3.27 3.33

College graduate ........................................................ 2.56 2.75 2.61 3.16

Characteristic
30 Monthly Labor Review June 1997

Measuring Job Security

Table 3. Employed contingent and noncontingent workers by selected characteristics, three alternative estimates, February

1995

[In thousands]

Estimate Estimate Estimate

1 2 3

Age and sex

 Total, 16 years and older .......................................... 123,208 2,739 3,422 6,034 117,174

16 to 19 years ............................................................. 5,635 456 521 645 4,990

20 to 24 years ............................................................. 12,421 685 758 1,196 11,225

25 to 34 years ............................................................. 32,138 712 940 1,587 30,551

35 to 44 years ............................................................. 34,113 507 678 1,265 32,848

45 to 54 years ............................................................. 23,980 225 326 760 23,219

55 to 64 years ............................................................. 11,370 103 127 355 11,014

65 years and older ...................................................... 3,551 49 73 225 3,326

 Men, 16 years and older .......................................... 66,290 1,350 1,689 2,995 63,295

16 to 19 years ............................................................. 2,820 197 234 291 2,528

20 to 24 years ............................................................. 6,634 329 366 586 6,049

25 to 34 years ............................................................. 17,566 354 465 833 16,733

35 to 44 years ............................................................. 18,317 274 352 615 17,703

45 to 54 years ............................................................. 12,694 91 144 341 12,353

55 to 64 years ............................................................. 6,187 72 83 215 5,972

65 years and older ...................................................... 2,072 32 44 115 1,957

Women, 16 years and older .................................... 56,918 1,389 1,733 3,039 53,879

16 to 19 years ............................................................. 2,816 259 287 354 2,461

20 to 24 years ............................................................. 5,786 356 392 610 5,176

25 to 34 years ............................................................. 14,572 358 475 754 13,818

35 to 44 years ............................................................. 15,796 233 326 651 15,145

45 to 54 years ............................................................. 11,286 134 181 419 10,866

55 to 64 years ............................................................. 5,183 32 44 141 5,043

65 years and older ...................................................... 1,479 17 29 109 1,370

 Race or ethnicity

White .......................................................................... 105,239 2,192 2,741 4,880 100,359

Black .......................................................................... 13,108 382 464 804 12,304

Hispanic origin ............................................................ 10,441 373 443 682 9,759

 Full- or part-time status

Full-time workers ........................................................ 99,240 1,449 1,835 3,444 95,796

Part-time workers ....................................................... 23,968 1,290 1,587 2,590 21,378

assigned to work by the firms change frequently.

The middle estimate adds the self-employed—both incorporated and unincorporated—and independent contractors in

a situation similar to that of the wage and salary workers of

estimate 1. That is, these workers expected to be, and had been,

in their respective employment arrangements for 1 year or less.

In addition, temporary help and contract company workers were

classified as contingent under this estimate if they had worked,

and expected to work, for the customers to whom they were

assigned for 1 year or less. For example, a “temp” secretary

who is sent to a different customer each week, but who has

worked for the same temporary help firm for more than 1 year

and expects to be able to continue with that firm indefinitely,

is classified as contingent under estimate 2, but not under estimate 1. In contrast, a “temp” who is assigned to a single client

for more than 1 year and expects to be able to stay with that

client for at least 1 more year is not counted as contingent

under either estimate.

In the third and broadest estimate, the limitation on how

long workers had held their jobs and expected to remain in

them was dropped for wage and salary workers; thus, this estimate includes almost any worker who believed that his or her

NOTE: Estimate 1: Wage and salary workers in their jobs for 1 year or less

who expected their jobs to last for an additional year or less. Estimate 2:

Workers in estimate 1, plus self-employed and independent contractors in

their jobs for 1 year or less who expected their jobs to last for an additional

year or less. Estimate 3: Self-employed and independent contractors in their

jobs for 1 year or less who expected their jobs to last for an additional year or

less, plus all wage and salary workers. Noncontingent workers are workers

who do not fall into any estimate of contingent workers. Details for the race

and Hispanic-origin groups will not sum to totals because data for the “other

races” group are not presented and Hispanics are included in both the white

and black population groups. Details for other characteristics may not sum to

totals due to rounding.

Contingent workers

Characteristic Noncontingent

workers

Total

employed
 Monthly Labor Review June 1997 31

job was temporary or who did not expect the job to continue.

That is, the estimate effectively includes all wage and salary

workers who did not expect their employment to last, except

for those who, for personal reasons, expected to leave jobs

that they would otherwise be able to keep. For example, a

worker who had held a job for 5 years could be considered

contingent if he or she now viewed the job as temporary. These

conditions on expected and current tenure were not relaxed

for either the self-employed or independent contractors.

Several pieces of information were collected in the CPS

supplement from which the existence of a contingent employment arrangement could be discerned: whether the worker

expected that the job was temporary or would not continue,

how long the worker expected to be able to hold the job, and

Table 4. Employed workers with alternative and traditional work arrangements, by selected characteristics, February 1995

 [In thousands]

Workers with alternative arrangements

Total Inde- On-call Temporary Workers

employed pendent workers help provided

contrac- and day agency by

tors laborers workers contract

 firms

 Age and sex

 Total, 16 years and older.. ................................ 123,208 8,309 2,078 1,181 652 111,052

 16 to 19 years ..................................................... 5,635 125 165 62 16 5,267

 20 to 24 years ..................................................... 12,421 197 261 233 83 11,649

 25 to 34 years ..................................................... 32,138 1,639 511 403 254 29,357

 35 to 44 years ..................................................... 34,113 2,559 492 251 152 30,679

 45 to 54 years ..................................................... 23,980 2,099 326 143 | 77 21,344

 55 to 64 years ..................................................... 11,370 1,131 191 68 44 9,938

 65 years and older .............................................. 3,551 559 132 21 27 2,817

 Men, 16 years and older ................................... 66,290 5,595 1,042 557 466 58,678

 16 to 19 years ..................................................... 2,820 71 85 35 9 2,620

 20 to 24 years ..................................................... 6,634 135 154 135 42 6,170

 25 to 34 years ..................................................... 17,566 1,051 270 198 194 15,877

 35 to 44 years ..................................................... 18,317 1,746 245 91 124 16,122

 45 to 54 years ..................................................... 12,694 1,389 141 52 37 11,083

 55 to 64 years ..................................................... 6,187 795 76 33 34 5,248

 65 years and older .............................................. 2,072 409 70 13 27 1,559

 Women, 16 years and older ............................. 56,918 2,714 1,036 624 186 52,373

 16 to 19 years ..................................................... 2,816 54 80 27 7 2,647

 20 to 24 years ..................................................... 5,786 63 107 98 40 5,480

 25 to 34 years ..................................................... 14,572 588 242 205 60 13,481

 35 to 44 years ..................................................... 15,796 813 247 160 28 14,557

 45 to 54 years ..................................................... 11,286 710 184 91 41 10,261

 55 to 64 years ..................................................... 5,183 336 115 34 10 4,689

 65 years and older .............................................. 1,479 150 63 9 — 1,258

 Race or ethnicity

 White. ................................................................. 105,239 7,671 1,745 859 541 94,473

 Black .................................................................. 13,108 416 229 257 76 12,143

 Hispanic origin .................................................... 10,441 431 259 134 55 9,566

 Full- or part-time status

 Full-time workers ................................................ 99,240 6,179 945 938 548 90,683

 Part-time workers ............................................... 23,968 2,130 1,134 242 104 20,368

how long the worker had held the job. For workers who had a

job with an intermediary, such as a temporary help agency or a

contract company, information was collected both about their

employment at the place the intermediary assigned them to

work and about their employment with the intermediary itself.

The key factor used to determine if a worker’s job fit the

conceptual definition of “contingent” was whether the worker

believed that the job was temporary or would not continue.

The first questions asked in the supplement were as follows:

1. Some people are in temporary jobs that last only for a

limited time or until the completion of a project. Is your job

temporary?

2. Provided the economy does not change and your job

NOTE: Workers with traditional arrangements are those who do not fall into

any of the “alternative arrangements” categories. Details may not sum to total employed because a small number of workers are both “on call” and “provided by contract firms.” Details for the race and Hispanic-origin groups will

not sum to totals because data for the “other races” group are not presented

and Hispanics are included in both the white and black population groups.

Dash indicates data base too small to meet publication criteria.

Characteristic

Workers

with

traditional

arrangements
32 Monthly Labor Review June 1997

Measuring Job Security

performance is adequate, can you continue to work for your

current employer as long as you wish?

Respondents who answered “yes” to the first question or

“no” to the second were then asked a series of questions to

distinguish persons who were in temporary jobs from those

who, for personal reasons, were temporarily holding jobs that

offered the opportunity of ongoing employment. For example,

students holding part-time jobs while in school might view

those jobs as temporary, because they may intend to leave

them at the end of the school year. The jobs themselves, however, would be filled by other workers once the students leave.

Jobs were defined as being short term or temporary if the

employee was working only until the completion of a specific

project, temporarily replacing another worker, being hired for

a fixed period, or filling a seasonal job available only during

certain times of the year, or if other business conditions dictated that the job was short term. Individuals who expected to

work at their current job for 1 year or less for personal reasons, such as returning to school, retiring, or obtaining another job, were asked if they could continue working at that

job were it not for that personal reason. If they could not do

so, they would be classified as contingent, provided that the

other conditions of the definition were met.

To further ascertain whether a job was temporary, workers

also were asked how long they expected to stay in their current job and how long they had been with their current employer. The rationale for asking how long an individual expected to remain in his or her current job was that being able

to hold a job for 1 year or more could be taken as evidence of

at least an implicit contract for ongoing employment. In other

words, the employer’s need for the worker’s services was not

likely to evaporate anytime soon. By the same token, the information on how long a worker had been with the employer

could show whether a job was ongoing. A person’s having

remained with an employer for more than 1 year could be

taken as evidence that, at least in the past, the individual had

an explicit or implicit contract for continuing employment.

Some of the major findings regarding the characteristics

of contingent workers are that they tended to be young and

were slightly more likely to be women and black. Also, the

majority of those in contingent jobs would have preferred more

permanent employment arrangements.12 (See table 3.)

The February 1995 survey also produced estimates of the

numbers of workers in several “alternative employment arrangements,” including persons working as independent contractors and on-call workers, as well as those working through

temporary help agencies or contract companies. According

to the survey, 8.3 million workers (6.7 percent of the total

employed) said that they were independent contractors, 2.0

million (1.7 percent) worked “on call,” 1.2 million (1.0 percent) worked for temporary help agencies, and 652,000 (0.5

percent) worked for contract firms that provided the worker’s

services to one customer at that customer’s work site. Contingent employment was defined separately from these four types

of employment arrangements, although an individual’s employment could both be contingent and fall into one of the

alternative employment categories.

The characteristics of workers in the four alternative employment arrangements identified in the survey varied considerably. (See table 4.) For example, independent contractors were substantially more likely than workers in traditional

arrangements to be men, white, and at least 25 years old; in

contrast, workers paid by temporary help agencies were more

likely than workers in traditional arrangements to be women,

young, and black. Workers provided by contract firms were

disproportionately male. Most on-call workers and workers

paid by temporary help agencies would have preferred to be

in traditional work arrangements. In stark contrast, more than

4 out of 5 independent contractors preferred their current work

arrangements.

While the February 1995 supplement provided a great deal

of new information about workers in contingent and alternative employment arrangements, repetition of the survey (scheduled for February 1997) will be necessary to determine whether

such employment arrangements are increasing.

Footnotes

1

 See, for example, Richard Belous, The Contingent Economy: The

Growth of the Temporary, Part-time and Subcontracted Workforce (Washington, National Planning Association, 1989); Flexible Workstyles: A Look

at Contingent Labor, Conference Summary (U.S. Department of Labor,

Women’s Bureau, 1988); New Policies for Part-time and Contingent Workers (San Francisco, New Ways to Work, 1992); “The Downsizing of

America,” The New York Times, Mar. 3–Mar. 9, 1996; and Lance Marrow,

“The Temping of America,” Time, Mar. 29, 1993. 2

 The material regarding the contingent and alternative employment

supplement previously appeared in Contingent and Alternative Employment Arrangements, Report 900 (Bureau of Labor Statistics, August 1995);

and in Anne E. Polivka, “Contingent and alternative work arrangements,

defined,” Monthly Labor Review, October 1996, pp. 3–9. 3

 For an analysis of a number of measures of self-perceived economic

insecurity not available in the CPS, see Jeff Dominitz and Charles F. Manski,

Perceptions of Economic Insecurity: Evidence from the Survey of Economic Expectations, NBER Working Paper No. 5690 (Cambridge, MA, National Bureau of Economic Research, July 1996). 4

 See, for example, Henry S. Farber, “Are Lifetime Jobs Disappearing?

Job Duration in the United States: 1973–1993.” Paper presented at the

NBER Conference on Research in Income and Wealth, Washington, December 1994; Kenneth A. Swinnerton and Howard Wial, “Is Job Stability Declining in the U.S. Economy?” Industrial and Labor Relations Review,

vol. 48, no. 2, January 1995, pp. 293–304; and Francis X. Diebold, David

Neumark, and Daniel Polsky, “Comment on Kenneth A. Swinnerton and

Howard Wial, ‘Is Job Stability Declining in the U.S. Economy?’” Industrial and Labor Relations Review, January 1996, pp. 348–52. 5

 James N. Brown and Audrey Light, “Interpreting Panel Data on Job

Tenure,” Journal of Labor Economics, July 1992, pp. 219–57. 6

 Barbara Means and Elizabeth F. Loftus, “When Personal History Re-
 Monthly Labor Review June 1997 33

peats Itself: Decomposing Memories for Recurring Events,” Applied Cognitive Psychology, vol. 5, July–August 1991, pp. 297–318. 7

 All computations reported here are weighted so that they are nationally representative of the age cohort. 8

 Workers are defined as those employed for pay in the week prior to

the interview, excluding the unincorporated self-employed. 9

 This interpolation procedure is what the Bureau of Labor Statistics

uses in published tables of percentiles for integer data. See Farber, “Are

Lifetime Jobs Disappearing?” for a more detailed discussion of the approach. For those who worked less than 1 year, the 1993 April CPS supplement does not provide any additional information (such as the number of

months continuously employed). For those in the “less than one year category,” a value of 1 year was assigned. 10 The NLSY cohort was 23 to 31 years old in 1988 and 28 to 36 years old in

1993. Hence, data on 28- to 31-year-old workers are available in both years. 11 The number of unweighted observations in the smallest subgroups (particularly for Hispanics and high school dropouts) is about 100. 12 The October 1996 issue of the Monthly Labor Review includes six

articles that present results from the CPS supplement on contingent and alternative employment.

LABSTAT Available via World Wide Web

LABSTAT, the Bureau of Labor Statistics public data base, provides current and

historical data for many BLS surveys as well as numerous news releases.

LABSTAT Public Access has introduced a new production Internet service over

the World Wide Web. BLS and regional offices programs are described using

hypertext pages. Access to LABSTAT data and news releases is provided by a link

to the BLS gopher server. The URL is:

http://stats.bls.gov/blshome.html

If you have questions or comments regarding the LABSTAT system on the Internet,

address e-mail to:

 labstat.helpdesk@bls.gov