The State of Languages in the U.S.: A Statistical Portrait
Where English-Speaking Adults Who Are Fluent in Another Language Acquired the Non-English Language, 2006
As of 2006 (the most recent year for which such data are available), the overwhelming majority of U.S. adults who reported they could speak a non-English language acquired that language at home. Only a small percentage (16.3%) acquired the language at school, reflecting the challenges faced by Americans of developing language proficiency after childhood.