Data and measurement problems have complicated the debate over trends in jo
b instability in the United States. We compare two cohorts of young white m
en from the National Longitudinal Surveys (NLS), construct a rigorous measu
re of job change, and confirm earlier findings of a significant increase in
job instability. We then benchmark the NLS against other main data sets in
the field and conduct a thorough attrition analysis. Extending the analysi
s to wages, we find that the wage returns to job changing have both decline
d and become more unequal for young adults, mirroring trends in their long-
term wage growth.