Comparing ACS Data

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Comparing ACS Data

The strength of the American Community Survey (ACS) is in estimating characteristic distributions. If you are looking for population totals, we recommend the 2010 Census or Population Estimates Program.

It is also important to keep in mind that all ACS data are estimates. We collect data from a sample of the population in the United States and Puerto Rico rather than from the whole population. To help you interpret the reliability of the estimates, the Census Bureau publishes a margin of error (MOE) for every ACS estimate.

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Can I compare ACS estimates?

Yes	Compare non-overlapping datasets (example: compare 2005-2009 ACS 5-year estimates to 2010-2014 ACS 5-year estimates).
No	Do not compare overlapping datasets (example: do not compare 2005-2009 ACS 5-year estimates to 2006-2010 ACS 5-year estimates).

Because ACS variables change over time, some areas and subjects must be compared with caution, or not compared at all. Use the years in the tabs below to get yearly guidance on specific topics/subjects.

Can I compare ACS estimates with 2010 Census?

Yes

Compare basic characteristics (sex, age, race, Hispanic origin, and homeowner status); other questions were not asked on the 2010 Census.

In general, use ACS to obtain population characteristics (percents, means, medians, and rates) rather than estimates of population totals. Use numbers from the 2010 Census to obtain counts of the population and their basic characteristics (sex, age, race, Hispanic origin, and homeowner status).

Use data from the Census Bureau's Population Estimates Program in the years between censuses. The Census Bureau's Population Estimates Program produces official population estimates for the nation, states, counties, cities and towns, plus housing unit estimates for states and counties.

Can I compare ACS estimates with Census 2000?

Yes

Compare ACS 1-year, 3-year or 5-year estimates with Census 2000 data.

However, differences in the universe, question wording, residence rules, reference periods, and the way in which the data are tabulated can impact comparability with Census 2000.

Use our Table Comparison Spreadsheet (.xls) to check for a comparable table for your topic of interest. It's searchable by ACS table numbers or Census 2000 table numbers. Note: we discontinued the Table Comparison Lookup Tool, and this spreadsheet will no longer be updated after the 2013-2017 ACS 5-year release.

Comparison Guidance by Year

2019

2019 Comparison Guidance

Learn more about comparing the 2019 ACS with Census 2000, 2010 Census, and 5-year to 5-year estimates.

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