How the figures are built

All expenditure data originates from the Independent Parliamentary Expenses Authority (IPEA), published quarterly and mirrored on data.gov.au. Each parliamentarian profile links back to the specific quarterly release it draws from.

Figures are work expenditure reported by IPEA — travel, office costs, and the other categories in the IPEA extract — expressed in Australian dollars. Each line item is recorded against the parliamentarian, the reporting quarter, and IPEA's own category and sub-category.

Salary and superannuation are modeled separately based on Remuneration Tribunal determinations, and are shown as a distinct remuneration breakdown on individual parliamentarian profiles to provide complete cost-of-office context.

Some quarters contain adjustments or reimbursements that appear as negative amounts; these are preserved as reported rather than discarded, so totals reconcile with IPEA.

An important distinction: work expenditure is reported directly by IPEA, but salary, superannuation and allowances are modelled by us from Remuneration Tribunal determinations. They are best-effort approximations shown to give cost-of-office context, and are flagged as under development on each profile. They should be read as estimates, not authoritative pay records.

Each quarterly figure combines the base parliamentary salary, any additional office loading (Prime Minister, Minister, Speaker, and so on), the electorate allowance and a vehicle allowance. Superannuation is the Commonwealth's 15.4% accumulation contribution on base salary plus office loading (allowances are excluded). Annual rates are divided by four to express a quarter.

The model makes these simplifying assumptions, each of which can move a figure:

• Electorate allowance is applied at the baseline rate ($39,700/year) for everyone. In reality House members receive more for geographically larger electorates; that scaling is not yet modelled.
• Vehicle allowance assumes all members take the $19,500/year cash-in-lieu entitlement. IPEA car / COMCAR expense lines are treated as separate travel costs (taxis, cars-with-driver), not a substitute for the allowance.
• Committee, whip and minor office-holder loadings are not yet tracked.
• Presiding officers — the Speaker of the House and the President of the Senate (and their deputies) — are elected by the chamber rather than appointed to the ministry. Our role data is sourced from ministry & shadow-ministry lists, so these offices and their loadings are not currently captured; those members show base salary until we add a dedicated source.
• Shadow ministers are paid the base backbench salary (they receive no ministerial loading). Only the Leader of the Opposition carries a modelled loading; the smaller loadings for the Deputy Leader, the Senate opposition leaders, the Manager of Opposition Business and the whips are not yet tracked.
• Mid-quarter role changes are modelled on the most recent active role in the quarter — there is no daily pro-rata split.

Defined-benefit pensions (PCSS). Members first elected before 9 October 2004 belong to the closed Parliamentary Contributory Superannuation Scheme — a lifetime indexed pension funded from consolidated revenue, not a 15.4% accumulation contribution. Its true cost is an actuarial accrual that is generally higher than standard super and is never zero. Rather than show a misleading blank, we display an indicative notional estimate at the 29.3%-of-salary notional employer contribution rate from the actuarial PCSS Long Term Cost Report. This is a scheme-wide average — an individual's real entitlement depends on their years of service and final salary — so it is clearly flagged and deliberately kept out of the headline taxpayer-cost total, never summed with the hard IPEA figures.

The smallest unit is a single reporting quarter. The time-period selector also offers rolling totals — last 6 / 9 / 12 months, 2 / 3 / 5 years, and all time — computed by summing each parliamentarian's expenditure across the relevant consecutive quarters. A "quarters on record" count shows how many quarters a person appears in within the window, which is lower for those who entered or left Parliament mid-window.

Parliamentarians are keyed on a stable identity (person_key) so that name variants, honorifics, and title changes across years all resolve to a single person — avoiding the duplicate-entry problem that plagues naive name matching.

Party names in the source data appear in many forms (e.g. "ALP", "Australian Labor Party (ALP)", "The Nationals"). We canonicalise these to one consistent label per party for filtering and display. For members who have changed party over time, we show their most recent party.

On a profile, rank is the parliamentarian's position by expenditure among all parliamentarians in that quarter, and vs median compares them to the middle of the field that quarter. These are descriptive, not evaluative.

New quarters are added after IPEA publishes them. The dataset is otherwise static — historical quarters do not change once released.

Raw totals are not normalised for electorate size, remoteness, or time in office, so they are not a fair like-for-like comparison — a remote-state senator will legitimately spend more on travel than an inner-city member. Per-capita and per-sitting-day context are candidates for future releases.

Salary, superannuation and allowance figures are modelled estimates, not IPEA-reported amounts, and carry their own assumptions and limitations — see the Salary, superannuation & allowances section above for the full breakdown.