groups; thus, BLS publications cannot be used to track work experience of minors, for whom the legal restrictions on child labor have been imposed. Furthermore, 19-year-olds and many 18-year-olds have finished high school, so their employment patterns can be expected to differ from those of adolescents still in high school. Aggregating the data for 16-to 19-year-olds obscures these differences. The official figures also exclude individuals who work fewer than 15 hours per week without pay in family-operated enterprises, a group that is likely to include many children and adolescents.
The CPS collects information on all the members of each household from one responding adult, so information about hours of work by adolescents does not come from adolescents themselves. It is possible that adults and adolescents would give different answers, not only for the number of hours worked by the adolescent, but also for whether the adolescent worked or not. In fact, Freeman and Medoff (1982) found that parents systematically reported that their children worked fewer weeks per year than the children reported. Obtaining information from the CPS on subpopulations of adolescents is also problematic. Pallas (1995) notes that the number of minorities enrolled in grades 10 to 12 in the sample in any given year is not large; therefore, statistical estimates about them are subject to large sampling errors. Disabled youngsters are not identified in the CPS, so no estimates are available for them.
A number of national longitudinal surveys, such as the National Longitudinal Survey of Youth, the National Educational Longitudinal Survey, and the National Longitudinal Study of Adolescent Health, collect information on young people, including their employment experience (see Table 2-1 and Appendix B for details about these surveys). Unlike the CPS, which provides a snapshot of youngsters' employment at a particular time, longitudinal surveys allow researchers to study the complex patterns of young people's employment over time. Youngsters may start to work in informal jobs (e.g., mowing lawns, babysitting) or in family businesses and family farms at fairly young ages. As they move through their teens, they are likely to move from job to job, working different numbers of hours at different times.
Surveys suggest that most youth are employed at some time dur-