Why do fewer agricultural workers migrate now?

The share of agricultural workers who migrate within the United States has fallen by approximately 60% since the late 1990s. To explain this decline in the migration rate, we estimate annual migration-choice models using data from the National Agricultural Workers Survey for 1989-2009. On average, over the last decade of the sample, one-third of the fall in the migration rate was due to changes in the demographic composition of the workforce, while two-thirds was due to changes in coefficients ("structural" change). In some years, demographic changes were responsible for half of the overall change.