Every now and then, for more efficient allocation of resources, the Government may collect data from individuals or households about their demographic characteristics, similar to age, gender, and country of birth, in addition to their socio-economic characteristics, similar to income, occupation and spend. A few of these data are then aggregated by geographic regions and made available to the general public.

In Australia where I live, the Government through the Australian Bureau of Statistics (ABS) calibrates an index called the Index of Economic Resources (IER), which scores the relative socio-economic status of a geographic region using a variety of variables sourced from the 5-yearly Census data collection.

IER may be aggregated by various digital boundaries which divide Australia into geographic regions of various sizes. For example, the State boundary (dashed line in Image 1) divides Australia into 8 States and Territories, whereas the Statistical Area 1 (SA1) boundary (in Image 2) divides Australia into rather more granular regions, at times a cluster of just quite a few streets.

Upon checking the IER in numerous regions on an interactive map provided by the ABS, as shown in the pictures below, I discovered that IER is kind of different by regions even at a street level, and I ponder what often is the drivers for this.