Source and Methodology
We have defined limited English proficient (LEP) individuals as the population 5 years or older who self-identify as speaking English less than "very well" according to the U.S. Census 2008-2012 American Community Survey 5-Year Estimate data. Total LEP population equals the sum of all individuals who speak a language other than English and speak English less than "very well." We have calculated the share of LEP individuals by tabulating LEP populations as a percentage of the total population of the statistical area. For more information on the underlying data, including margins of error, see U.S. Census Bureau - ACS 2012 Table: B16001 5-Year Estimate Language Spoken At Home By Ability To Speak English For The Population 5 Years And Over. The Margin of Error information is downloadable from the Accessible Map App Site using the "Download State/County Level Data" buttons. The Margin of Error fields are indicated by the symbol: ±.
Click here for more information about how the Census and the American Community Survey collects data on language use and English-speaking ability, including the creation of language groups and categories. We also welcome feedback on our mapping tool.