Your Postcode Wasn't Built to Describe You

Four digits that can cross a state border — and why a postcode on a parcel is not always identical to the area on a statistics map. Sam follows Australia's 1967 rollout, America's Mr ZIP and the difference between organising deliveries and describing people.

Originally planned for 11 October; this delayed episode carries its actual publication date. The household example is hypothetical. Historical statistics are identified as historical, not current totals.

Sources:
Australia Post — 1967 rollout, sorting and public booklets:
https://collectables.auspost.com.au/community-and-events/articles/postcodes-turn-50
Australia Post — history, 1968 adoption and envelope sizes:
https://auspost.com.au/about-us/corporate-information/our-history
Australia Post — allocation and changes:
https://auspost.com.au/about-us/corporate-information/our-organisation/policies/assignment-of-postcodes
USPS — ZIP code introduction and structure:
https://facts.usps.com/decoding-the-zip-code/
USPS — Mr ZIP:
https://facts.usps.com/mr-zip/
The Postal Museum — Norwich trial and national rollout:
https://staging1.postalmuseum.org/blog/why-do-we-have-postcodes/
ABS — postal codes are designed for mail delivery:
https://www.abs.gov.au/statistics/statistical-geography/frequently-asked-questions
ABS — Census geography glossary and postal-area approximations:
https://www.abs.gov.au/census/guide-census-data/geography/census-geography-glossary
ABS — historical cross-border examples:
https://www.abs.gov.au/ausstats/abs%40.nsf/Latestproducts/2916.0Main%20Features202016/%24File/2016POA_readme.pdf