State Completion Lag
State Completion Lag (21840) measures, for each state and territory, whether the pipeline of dwellings under construction is taking longer to clear: the change over the year in months of pipeline, the stock of dwellings under construction divided by the past year’s completions and expressed in months. Higher readings mean completion lags lengthening. It publishes eight readings, each against the jurisdiction’s own history, and belongs to State & Territory Conditions (21800). The national level reading is Construction Completion Lag (21290).
The input is the change over the year in months of pipeline, not its level: the level rises over the decades as building shifts towards apartments, which take longer to complete, so the level is shown as context only. Both inputs are ABS original series; four quarters of completions remove the dip in completions each March quarter, so no seasonal baseline is needed. The Northern Territory and the ACT are small and volatile (baseline standard deviations of 4.45 and 5.28 months, against 1.44 to 3.74 elsewhere). ABS revises building activity as later returns arrive, and the June quarter 2026 edition revised the March quarter; the stored history carries the revision.
Primary metric: Node Z-Score by state (Z21840,s)
Position. Each reading is ranked against the state’s own 161 quarters from June 1986, the first quarter with a year-earlier level to compare; every position is empirical.
| Input | Source | Frequency | Coverage |
|---|---|---|---|
| Dwellings under construction, by state | ABS Building Activity, Australia (8752.0), Table 77, original | Quarterly | September quarter 1984 to June quarter 2026 |
| Dwellings completed, by state | ABS Building Activity, Australia (8752.0), Table 38, original | Quarterly | September quarter 1984 to June quarter 2026 |
| Dwellings commenced, by state (context) | ABS Building Activity, Australia (8752.0), Table 34, original | Quarterly | September quarter 1984 to June quarter 2026 |
Tier-1 sovereign statistical releases. No commercial data provider dependency exists within this node.
Year to June 2026, ordered by reading. Months of pipeline is the level at each June; the change is the input. Each z is against the state’s own 2011–2025 average; each position ranks the state against its own 161 quarters. The last column is completions divided by commencements over the past four quarters: below 1.00, work is starting faster than it is finishing.
| State | Months of pipeline, June 2025 | June 2026 | Change (months) | Q2 2026 Z | Position (of 161) | Q1 2026 Z | Completions ÷ commencements |
|---|---|---|---|---|---|---|---|
| Queensland | 14.66 | 18.22 | +3.55 | +1.7579σ | 97.5 | +2.1575σ | 0.75 |
| Western Australia | 12.35 | 17.81 | +5.46 | +1.4014σ | 96.2 | +0.8702σ | 0.77 |
| Australian Capital Territory | 14.95 | 19.77 | +4.82 | +0.8511σ | 86.9 | +0.3930σ | 0.77 |
| Tasmania | 10.57 | 11.83 | +1.26 | +0.7224σ | 80.6 | +1.0148σ | 0.93 |
| South Australia | 13.20 | 13.96 | +0.76 | +0.2062σ | 67.5 | −1.0575σ | 0.89 |
| Victoria | 13.20 | 13.52 | +0.32 | +0.1205σ | 56.2 | +0.8592σ | 0.98 |
| Northern Territory | 14.14 | 11.72 | −2.42 | −0.6342σ | 16.2 | −0.4319σ | 0.88 |
| New South Wales | 21.31 | 19.03 | −2.28 | −1.1775σ | 7.5 | +0.7281σ | 0.96 |
One chart per state on the same scale (−3σ to +3σ), from March 2011. Each line is the state’s z against its own 2011–2025 average; the shaded band is the middle 80% of all its ranked quarters from June 1986.
Over the year to June 2026, completion lags lengthened in six of the eight jurisdictions, most in Queensland (14.66 to 18.22 months of pipeline, +1.7579σ, position 97.5) and Western Australia (12.35 to 17.81 months, +1.4014σ, the highest since June 2022). The ACT’s reading (+0.8511σ) is its highest since June 2024. In Queensland, Western Australia and the ACT, completions over the past year ran at about three-quarters of commencements (0.75 to 0.77): work is starting faster than it is finishing, so the stock under construction is growing relative to the rate at which it clears.
Lags shortened in New South Wales and the Northern Territory. New South Wales reads −1.1775σ, position 7.5, its lowest since September 2019: its pipeline fell from 21.31 to 19.03 months as completions ran close to commencements (0.96). It is shortening from a high level — 19.03 months is still the second-longest of the eight, after the ACT’s 19.77. The Northern Territory (−0.6342σ) is at its lowest since March 2024.
Queensland’s reading is below its March quarter reading of +2.1575σ: its lag is still lengthening over the year, but by less than it was. South Australia moved from −1.0575σ in March to +0.2062σ, and Western Australia from +0.8702σ to +1.4014σ.
The national counterpart and the other state measures.
- All inputs are sourced from Tier-1 sovereign statistical releases (ABS)
- Each of the eight Z-scores (Q2 2026) is derived directly from that state’s inputs against its own 2011–2025 baseline, not manually entered or estimated
- Each position is an empirical percentile rank against the state’s 161 quarters from June 1986
- The use of the change rather than the level, the volatility of the two territories and the March quarter revision are disclosed
- No commercial data provider dependency exists within this node
