data.census.gov is the online source for American Community Survey and other data from the U.S. Census Bureau. Other specialized options for ACS data are also available.
Margin of Error (MOE) | Published along with ACS estimate (EST). Corresponds to a 90% confidence level. (See Compass for alternate confidence levels.) |
Confidence Interval (CI) | CI = (EST - MOE, EST + MOE) (expressed as a range) |
Standard Error (SE) | SE = MOE / 1.645 |
Coefficient of Variation (CV) | CV = (SE / EST) x 100 (expressed as a percent) |
The degree of uncertainty for an estimate arising from sampling variability is represented through the use of a margin of error. [...] The margin of error can be interpreted roughly as providing a 90 percent probability that the interval defined by the estimate minus the margin of error and the estimate plus the margin of error (the lower and upper confidence bounds) contains the true value." (Census Bureau)
Source: Downloaded and manipulated from Census Bureau, American FactFinder
Source: Census Bureau, When to use 1-year, 3-year, or 5-year estimates