Since 1790, the United States Census Bureau has conducted a national population count every 10 years, with the most recent being the 2010 Census. This decennial census collects basic demographic data on the sex, age, relationship, race and ethnicity of every resident and every household in the nation.
American Community Survey
The Census Bureau's American Community Survey (ACS) collects detailed data on education, poverty, migration, commute patterns, and income.
The ACS is a monthly survey of the United States population that replaces the "Long Form" questionnaire used in the 2000 Decennial Census. ACS estimates are available as 1 and 5-year averages with the 1-year data being the most current but least accurate and the 5-year data being the most accurate but least current.