ASGS SA4 2021 - GPC 2023

General Practitioner Catchment (GPC): Developed by the Australian Government Department of Health and Aged Care, GPCs are custom geographic areas built from ABS ASGS 2021 boundaries (SA1, SA2, SA3, UCL). These catchments provide a more accurate view of where patients access GP services. Statistical Area Level 4 (SA4): SA4s are the largest sub-state regions in the ASGS, constructed from SA3s. They are designed to reflect labour markets and the functional areas of capital cities, supporting the release of regional data such as the Quarterly Labour Force Survey. There are 108 SA4s across Australia, including codes for mobile or unlocated populations. SA4s aggregate to form Greater Capital City Statistical Areas and States/Territories.