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English Language Proficiency among the Foreign Born in the United States, 1980–2007: Duration, Age, Cohort Effects 1

This study employs pooled data from the 1980 through 2000 censuses and 2001 through 2007 American Community Survey data to study English language proficiency among foreign-born in a dynamic framework. Our findings show continuing significance of duration of stay and age at migration and declining English language proficiency across successive cohorts. Additionally, analysis enabled by availability of single-year data from 2000 to 2007 indicates acquisition of language proficiency as steepest during first 9 years upon arrival and for migrating age group 6–17. Further, we find significant differences by education, regions of origin, racial groups, and by regions of residence.