A previous version of this working paper was originally published as Fast Locations and Slowing Labor Mobility in November 2019.

These “fast locations” were the population growth destinations of the 20th century, where home attachments were once low but have increased as regional population growth has converged. Using a novel measure of home attachment, this paper estimates a structural model of migration that distinguishes moving frictions from home utility. Simulations quantify candidate explanations of the decline. Rising home attachment accounts for most of the mobility decline, and its effect is consistent with the observed spatial pattern. Population aging explains most of the remainder but in a more spatially neutral way. The paper then uses a stylized island economy model featuring endogenous home attachments to show that after a shock, gross migration returns to steady state much more slowly than net population change.