The U.S. Census Bureau’s American Community Survey (ACS) provides annual demographic data including educational attainment, foreign born population, language spoken at home, household income, and housing characteristics.
When using the American Community Survey’s data, it is best to use percentages rather than report actual numbers because the ACS is a survey of a small subset of the county’s population.
Census Bureau data, including data from the ACS, can be found on the Census Bureau’s data website.
The U.S. Census Bureau’s Decennial Census is conducted every ten years to count 100% of the county’s population. Census 2010 data can be found on the U.S. Census Bureau’s data website by typing “2010 Decennial Census Loudoun County, Virginia” in the search box.