April 1 is Census Day! The U.S. Constitution requires that the government make an “actual enumeration” (complete count) of all people in the United States every 10 years. In addition to the number of people in each household, the Census questionnaire includes questions about age, sex, race and national origins.
The population counts are used to determine representation in the U.S. Congress and in state and local voting districts. The counts are also used to allocate billions in federal, state and local government funding. From the Census data, we learn a lot about the population, as shown in the graphics below.
The population pyramid below shows the distribution of ages of Washington County residents and how they have changed over the last 70 years. The animation includes Census data from 1950
2010 and an estimate for 2018.