The federal Decennial Census has been conducted every 10 years since 1790. It is mandated by Article I, Section 2 of the U.S. Constitution, and is supposed to count every person living in the United States.
The Decennial Census, the Economic Census and the American Community Survey (ACS) provide information about the make-up of our nation crucial for Congress and the community leaders to make informed decisions that shape our democracy. Since 1790, the U.S. Census has been more than a simple head count- it has charted the growth and composition of our nation. This infographic details how the questions have evolved over time to address our changing needs.
Source: United States Census Bureau