21830 – State Supply Adequacy

State Supply Adequacy (21830) measures, for each state and territory, whether the dwelling stock is keeping pace with the population: population growth over the year less dwelling-stock growth over the year, in percentage points. Higher readings mean the population is growing faster than the stock of homes. It publishes eight readings, each against the jurisdiction’s own history, and belongs to State & Territory Conditions (21800). The national reading is Housing Supply Adequacy (21540).

Primary metric: Node Z-Score by state (Z_21830,s)

Position. Each reading is ranked against the state’s own 55 quarters since September 2012; every position is empirical.

Tier-1 sovereign statistical releases. No commercial data provider dependency exists within this node.

Year to March 2026, ordered by reading. Each z is against the state’s own 2011–2025 average; each position ranks the state against its own 55 quarters.

One chart per state on the same scale. Each line is the state’s z against its own 2011–2025 average; the shaded band is the middle 80% of its ranked quarters.

In the year to March 2026, population grew faster than the dwelling stock in three jurisdictions: the Northern Territory (+0.72 points, with the dwelling stock growing 0.78%), Western Australia (+0.64 points; population growth of 2.12%, the fastest of any jurisdiction) and Queensland (+0.18 points). In New South Wales and Victoria the two grew at almost the same pace. In the ACT (−0.60 points), South Australia (−0.33) and Tasmania (−0.27) the dwelling stock grew well ahead of population.

Against each state’s own history, the Northern Territory reads highest (+0.9625σ, position 74.1) and South Australia lowest (−1.0448σ, 13.0). South Australia’s reading has fallen in each of the past two quarters, from −0.40σ in September 2025, as population growth slowed to 0.97% while dwellings grew 1.30%. Western Australia’s persons per dwelling, 2.582, is the highest of its record.

Six of the nine series, including the national reading, peaked in 2023 after the border reopened; five reached their lows in 2021, while it was closed. Tasmania’s history differs: its highest readings were in 2016–2019, which is why its current reading sits below its average (−0.1101σ) yet above most of its quarters (position 68.5).

The national counterpart and the other state measures.