Why is the U.S. census conducted every ten years?

The U.S. census is conducted every ten years primarily to ensure that congressional representation is accurate. This decennial count is essential for determining the population of each state, which directly influences the apportionment of seats in the House of Representatives. The distribution of congressional seats is based on population data; therefore, a complete and accurate census is critical to guaranteeing that each state is fairly represented according to its population.

In addition to congressional representation, census data is vital for various government functions, including the allocation of federal funding, community planning, and the enforcement of civil rights laws. The emphasis on accurate representation underscores the importance of the census in sustaining the democratic process, ensuring that each citizen's voice is reflected in the legislative body.

The other options address interesting aspects of the census but do not capture its primary purpose. Maintaining historical records and monitoring economic growth are secondary effects of the data collected, while providing data for tax audits does not align with the primary objective of the census.