The decennial census has been conducted in years ending in "0" since 1790. Accordingly, a census is taken every 10 years.
Since the decennial census is taken every 10 years the Census Bureau initiated the American Community Survey (ACS) to sample subsections of the population for daily polling, business intelligence, and statistical inquisitiveness purposes. The ACS is a rolling sample survey that gets its annual data from three annual datasets, that being the 1 year, 3 year, and 5 year estimates - although the 3 year estimates were discontinued after 2013. Knowing the difference between the decennial census and ACS surveys will help when browsing data.
Rider University Moore Library is a Federal depository library since 1976 and is now collecting mostly digital federal documents. This Guide is created to help you access and use the current and the past U.S. census.
Since it is the obligation of the Census Bureau to provide the most complete and accurate population count possible for apportionment of the seats in the U.S. House of Representatives, it is important that the Census Bureau recognize many kinds of geographic areas. To learn more about the way the Census Bureau determines geographic subdivisions you can reference the Geographic Areas Reference Manual.
There are two kinds of geographic entities to be aware of when researching census statistics. Below is a list of each entity and the geographic areas each entity covers, as well as the Standard Hierarchy of Census Geographic Entities diagram.
1) Legal and administrative entities
2) Statistical entities
The Guide takes resources from University of Denver LibGuide https://libguides.du.edu/c.php?g=90231&p=7251841
