# Episode 4: One-Year or Five-Year

Distinguishes ACS 1-year and 5-year products and safe comparisons.

## Sources and attribution

- [Discovering the American Community Survey](https://www.census.gov/data/academy/courses/discovering-the-american-community-survey.html) by Vicki Mack and U.S. Census Bureau; published by U.S. Census Bureau Census Academy.
- [Understanding and Using American Community Survey Data: What All Data Users Need to Know](https://www.census.gov/content/dam/Census/library/publications/2020/acs/acs_general_handbook_2020.pdf) by U.S. Census Bureau; published by U.S. Census Bureau.
- [About Torrance](https://www.torranceca.gov/Government/About-Torrance) by City of Torrance; published by City of Torrance.

This episode is an independent study production based on the sources listed above. Source attribution does not imply affiliation, approval, sponsorship, or endorsement by any author, publisher, or institution.

## License

U.S. Government work not subject to copyright in the United States; third-party material excluded; Copyrighted local government webpage; facts summarized with attribution, no expressive text reproduced

## Production notes

Independent educational production. Not an official U.S. Census Bureau or City of Torrance course, not endorsed or certified by either, and not legal or statistical advice. The narration is an original synthesis. Verify current law, guidance, course requirements, and source terms before relying on it.

Stable episode ID: `fff2bb5f-41cf-5e16-9619-7faff5ca9286`

## Transcript

This episode focuses on ACS period estimates. Census data becomes useful when the population, measure, geography, and time period are stated before anyone searches for a number.

ACS one-year and five-year products measure periods of different length. A one-year estimate uses twelve months of collected data and favors currency. A five-year estimate combines sixty months, offers broader geographic coverage, and generally favors precision.

The five-year label names the final year, but the estimate does not describe that date alone. It describes the entire collection period. Do not call it a rolling average unless the specific statistic and method justify that language.

Compare like products and nonoverlapping periods when possible. A one-year estimate and a five-year estimate are not direct substitutes. Product choice should follow geography, precision needs, and the decision's tolerance for older observations.

Torrance application segment. This local application is separate from the Census Academy instruction. The cited City of Torrance primary source is About Torrance, published at https://www.torranceca.gov/Government/About-Torrance. For a local analysis, date every local fact and avoid comparing a current City count directly with a multi-year ACS period estimate. Do not present City policy or administrative records as Census Bureau findings, and do not present a federal estimate as adopted City policy.

Keep a reproducibility packet containing the question, source URLs, exact vintage, table or query, geography codes, raw result, calculations, and uncertainty note. This narration is an original synthesis of cited U.S. Census Bureau government works and separately cited City of Torrance material. Third-party videos, software, graphics, and linked works are excluded. This product uses Census Bureau information but is not endorsed or certified by the Census Bureau. It is not an official City product and does not imply City endorsement.