Overview

SA1s will replace Collection Districts (CDs) as the smallest geography for which detailed census data is released. They are built from whole Mesh Blocks, which aggregate cleanly to form an SA1 in a one-to-many parent/child relationship

Statistical Area Level 1 (SA1) vs. Collection Districts

Example: Ryde, NSW

• 36 x Collection Districts in 2006
• 47 x Statistical Local Area 1 in 2011

Pros

• Population-based rather than household-based.
  Aim: 400 Persons (200 min, 800 max)
• Defined using infrastructure and landmarks.
  Aim: Stability between censuses over a long period of time
• Generally much better granularity.
  54,805 SA1s versus 38,704 CDs
• Mesh Blocks now fit cleanly within SA1s with no overlaps.
  Unlike 2006, where MBs were an experimental geography and had no relationship to any other geography

Cons

• No official concordance to Collection Districts.
  Viewing 2006 data at a SA1-level will be a challenge, due to the significant structural difference between SA1s and CDs

More information about SA1s

For a detailed description of SA1s, please view the Statistical Area Level 1 (SA1) page on the ABS website.