Australia's government debt was 77.6% in 2025, and a year out it is expected to be about the same as that.
2026
77.6%
74.2% to 81.0%
Usually within 5.4 of the outcome at this range
2026
77.6%
74.2% to 81.0%
Usually within 5.4 of the outcome at this range
The ranges are not a feeling about confidence. They are how far this method has actually been off before: half of past outcomes landed inside them, and half outside. The nearer one is tighter because the near future genuinely is more knowable than the far one.
% of GDP. Sources: Australia — OECD via DBnomics. Retrieved 2026-09-17. Everything after the dotted line is a forecast, not a record. The shaded band is where this method has landed half the time in the past — so half the time, outside it. No language model produces any of these numbers.
How far off this forecast has usually been
Every method was replayed from each of the last three years' starting points, seeing only what was known at the time, and scored against what actually happened for Australia.
The forecast drawn above has landed within 5.35% of the outcome on average a year ahead, and within 5.35% a year ahead.
How far each forecasting method has been off in the past, and how often its stated range held.
Method
Usually off bya year ahead
Usually off bya year ahead
Its range heldit claims 50 in 100
vs. the simple rulebelow 1.00 is better
Assume last year repeats
4.21%
4.21%
5 in 10
1.00
Exponential smoothing
5.29%
5.29%
6 in 10
1.26
The middle of all methodsthe one drawn above
5.35%
5.35%
6 in 10
1.27
Theta
5.42%
5.42%
6 in 10
1.29
Automatic ARIMA
6.04%
6.04%
4 in 10
1.44
Australia, measured over the last 30 starting points. The last column compares each method against the simplest rule there is — assume this period repeats what it did a year ago. Below 1.00 means smaller errors than that rule, above it means worse. All of it is measured against today's revised figures rather than against what was known at the time, which flatters every method here a little.
Where the methods disagree
A year out the methods stop agreeing. The spread is not a flaw to be hidden: it is the honest size of what nobody knows yet, and it is why the chart above draws the middle of them rather than picking a favourite.
Australia, 2026. The dot is what each method expects, the bar how far it would not be surprised to be wrong. They are run on the same numbers and still land 0.0% apart, which is the honest size of the disagreement — and the reason the chart above draws the middle of them rather than picking a favourite.
Compare with other economies
This page is one country held still. To put Australia beside others, or to change the window, use the full chart — whatever you choose there stays in the address, so the view is the link.