Wage differentials, illustrated

NBER working paper (link): Do labor market changes help explain the decline in interstate migration in the US?

Interstate migration has decreased steadily since the 1980s. We show that this trend is not primarily related to demographic and socioeconomic factors, but instead appears to be connected to a concurrent secular decline in labor market transitions. We explore a number of reasons for the declines in geographic and labor market transitions, and find the strongest support for explanations related to a decrease in the net benefit to changing employers. Our preferred interpretation is that the distribution of relevant outside offers has shifted in a way that has made labor market transitions, and thus geographic transitions, less desirable to workers.