# Methodology — costofgovernment.com.au dataset (built 5 Nov 2026, Australia/Brisbane)

## 1. Definition of "cost of government"
**Cost of government = General Government sector Total GFS expenses (accrual basis)**, as published by the ABS in *Government Finance Statistics, Australia, 2024-25* (cat. no. 5512.0, released 21 Apr 2026). This covers operating costs (employees, superannuation, goods and services, depreciation), interest, social benefits, subsidies and grants. It excludes capital purchases (net acquisition of non-financial assets) and public corporations (e.g. state utilities, NBN Co). One ABS framework covers every jurisdiction, so the comparison across states is like-for-like.
- Period: financial years 2015-16 to 2024-25 (10 years). 2024-25 is the latest year the ABS has published as final.
- All values are **ABS-compiled outcomes, not budget estimates.** Budget-paper and MYEFO estimates are not included in this dataset.
- The ABS republishes the full 10-year series in each release, so earlier years reflect ABS revisions up to Apr 2026. They may differ slightly from older releases and from each government's own budget outcome reports, because the ABS standardises classifications across jurisdictions.

## 2. Jurisdictions and sectors
| Code | Series | ABS workbook |
|---|---|---|
| AUS | Total all levels of government, General Government (consolidated: Commonwealth + state + local + control n.f.d., with intergovernmental transfers eliminated) | 55120DO021 |
| CWTH | Commonwealth General Government | 55120DO002 |
| NSW, VIC, QLD, SA, WA, TAS, NT, ACT | State General Government (primary state comparison) | 55120DO003–010 |
| STATES_TOTAL | Total State General Government (consolidated across states) | 55120DO011 |
| state_local_* metrics | State and Local General Government for each state (adds councils) | 55120DO070–077 (ACT uses 010; ACT has no separate local government) |

## 3. Denominators (population)
- ABS Estimated Resident Population (ERP), persons, all ages, from the ABS Data API dataflow ERP_Q (National, state and territory population).
- **Choice:** ERP at **31 December** of each financial year (e.g. 31 Dec 2024 for 2024-25). That date is the midpoint of the July–June year and stands in for average population over the year. Documented on every row.
- Commonwealth and Australia figures use Australian ERP. State figures use that state's ERP.
- ERP for recent quarters is preliminary or revised and is subject to ABS rebasing after the 2026 Census.

## 4. Double-counting rules (intergovernmental grants, GST and HFE)
- **Never sum Commonwealth + state figures.** Commonwealth expenses include "Grant expenses to state governments" (2024-25: $152.2bn, including GST payments and specific-purpose payments), and the states then spend that money again. The **Australia total uses the ABS consolidated series (55120DO021)**, which eliminates these transfers: 2024-25 consolidated = $1,030.5bn, not $745.0bn + $409bn + local.
- Provided to support honest views:
  - `grants_to_states_and_local_nominal` (Cwth) and `expenses_excl_grants_to_states_per_person_nominal`: Commonwealth spending net of the money passed to states and councils.
  - `grants_received_nominal` (each state) = Current grants and subsidies + Capital grants revenue (mostly Commonwealth, including GST under horizontal fiscal equalisation) and `expenses_net_of_grants_received_per_person_nominal` = an **indicative**, derived "own-funded" figure. It is NOT an official ABS aggregate.
- State per-person spending is **gross** spending by that government, whoever funds it. NT, Tasmania and SA receive large GST/HFE shares, so their spending is not borne mainly by their own taxpayers. Each state row carries this note.

## 5. Taxpayer burden
- `tax_revenue_nominal` = GFS "Taxation revenue" in the same ABS operating statements. AUS = all levels consolidated. CWTH = Commonwealth (income tax, GST, excise and so on; GST is a Commonwealth tax in GFS). States = state taxes only (payroll, stamp duty, land tax and so on), **excluding** council rates. The state+local tax series was not extracted (gap; available in workbooks 070–077 if wanted).
- Per person = tax / ERP. This is an average across all residents, including children, not tax paid per taxpayer.

## 6. Households / families
- Household view = per-person figure x **ABS 2021 Census average number of people per household** (QuickStats): Australia 2.5; NSW 2.6; VIC 2.5; QLD 2.5; SA 2.4; WA 2.5; TAS 2.4; NT 2.8; ACT 2.5 (published to one decimal place).
- This is illustrative, applies one fixed Census value to all 10 years, and the per-person figure is always primary. It is not an estimate of what any family actually pays.

## 7. Real vs nominal
- Real = nominal x (CPI FY 2024-25 average / CPI FY average for the year). CPI = ABS All groups CPI, Original, Australia (dataflow CPI v2.0.0, index Sep 2025 = 100). FY average = mean of Sep, Dec, Mar and Jun quarter indexes. Results are in **2024-25 dollars**. (FY CPI: 2015-16 = 75.20; 2024-25 = 97.39.)
- The CPI measures household prices, not government input costs. The ABS GFS deflator was not applied (no published GFS-expenses deflator for each jurisdiction was used).

## 8. Caveats and series breaks
- **COVID:** 2019-20 to 2021-22 Commonwealth "Other subsidy expenses" jump ($63.0bn in 2019-20, $92.9bn in 2020-21; mostly JobKeeper), and state health spending also spikes. Flag these years on charts.
- 2020-21 ERP dip (closed borders) slightly raises per-person values.
- Expenses include non-cash items (depreciation, superannuation and interest valuation effects). Superannuation interest swings with discount rates.
- ABS GFS figures differ from the Commonwealth Final Budget Outcome and state budget outcomes because of sector coverage and classification. The ABS is used throughout for consistency. Treasury, Finance and state Treasury documents were NOT used as data sources in this build.
- Rounding: source in $m; derived per-person values to 2 decimals.

## 9. Exact sources (accessed 5 Nov 2026)
1. ABS, Government Finance Statistics, Australia, 2024-25 (5512.0), release page: https://www.abs.gov.au/statistics/economy/government/government-finance-statistics-annual/latest-release — workbooks 55120DO001, 002–011, 021, 070–077 (`https://www.abs.gov.au/statistics/economy/government/government-finance-statistics-annual/2024-25/55120DO0NN_202425.xlsx`), Table 1 Operating Statement.
2. ABS, National, state and territory population, ERP_Q: https://data.api.abs.gov.au/rest/data/ABS,ERP_Q,1.0.0/all
3. ABS, Consumer Price Index, CPI v2.0.0, key 1.10001.10.50.Q: https://data.api.abs.gov.au/rest/data/ABS,CPI,2.0.0/1.10001.10.50.Q
4. ABS, 2021 Census QuickStats, Australia and each state/territory: https://www.abs.gov.au/census/find-census-data/quickstats/2021/{AUS,1..8}
Raw copies are in `data/raw/`. The rebuild script is `data/build.py`.