Decennial census records are confidential for 72 years to protect respondents' privacy. Records from the 1960 to 2010 Censuses can only be obtained by the person named in the record or their heir after submitting form BC-600 or BC-600sp (Spanish). Individual census records from 1790 to 1950 are maintained by the National Archives and Records Administration, not the U.S. Census Bureau.
Decennial Census, 1940-2000: Everyone filled out the short form and a random sample filled out the "long form," which included the short form.
Short form = 100%
Sample size very large, 17 to 18%
The decennial census will continue to collect short form data.
ACS (American Community Survey): Replaced the decennial Census "long form."
Data collected all through year.
The ACS is collected by mail, telephone, and visits.
Addresses are chosen at random within areas.
5-year, 3-year, and 1-year estimates* are produced.
The sample size is 2.5% of households per year. The Margin of Error for the data is large.
Multiple years of data create more reliable estimates for smaller locations.
Measures the characteristics, not counts of the population.