Nineteen Economies, a 165-Point GDP Gap Public finance projections through 2031 cover nineteen major advanced and emerging economies. They paint a picture of a fragmented fiscal world. On one side, Ja

Nineteen Economies, a 165-Point GDP Gap

Public finance projections through 2031 cover nineteen major advanced and emerging economies. They paint a picture of a fragmented fiscal world. On one side, Japan is set to carry gross public debt equivalent to 192.8% of its GDP. On the other, Turkey would remain at 27.5%. The gap thus reaches nearly 165 percentage points of GDP: Japan's relative indebtedness would be roughly seven times that of Turkey.

The dispersion is not limited to these two extremes. Across the nineteen countries, the arithmetic average of projected gross debt comes out at around 86% of GDP. The median stands at 77.7%, the level projected for India. An average above the median indicates a distribution pulled upward by a few very large debtors. Seven economies exceed the 100% threshold: Japan, the United States (142.1%), Italy (136.1%), China (126.8%), France (120.7%), Brazil (106.5%), and Canada (103.5%). The United Kingdom follows close behind at 102.6%, bringing to eight the number of countries beyond this symbolic threshold.

For the analyst, this first observation is not enough. A gross debt ratio measures a stock of liabilities. It says nothing about the assets held against them, the economy's capacity to generate revenue, or the growth dynamics that will—or will not—finance this stock. It is by cross-referencing indicators that the true structural divergences emerge.

Gross Debt, Net Debt: What the Gap Reveals

Net debt subtracts from gross debt the financial assets held by public administrations. The gap between the two thus serves as an approximation of the thickness of the public financial "cushion." Across the fifteen countries for which both measures are available, this gap varies dramatically. It brings to light very different families of fiscal models.

Canada, Japan, South Korea: The Asset-Cushioned Powers

Canada's case is the most striking in the panel. With projected gross debt of 103.5% of GDP, Ottawa ranks among the most indebted economies in gross terms. Its net debt, however, would amount to only 10.4%, the lowest level among the fifteen countries. The gap, exceeding 93 points, reflects a massive accumulation of public assets relative to liabilities. Judging Canada on its gross ratio alone would therefore lead to a major analytical misreading.

Japan presents a comparable configuration, in different proportions. Its projected net debt of 122.8% remains very high, but is about 70 points below its gross debt. This considerable differential partly relativizes the 192.8% figure. It also confirms that, even adjusted for its assets, the Japanese state remains one of the most indebted in the panel, just behind Italy.

South Korea offers a third example, perhaps the most instructive. Its gross debt would reach 63.1% of GDP, an intermediate level. Its net debt would fall to 12.9%, a gap of about 50 points. Seoul thus ranks, alongside Canada, among the states whose net financial position appears strongest, despite non-negligible gross indebtedness.

South Africa, Indonesia, Turkey: Debt Without a Cushion

At the opposite end, several emerging economies show nearly identical gross and net debt. In South Africa, projected gross debt of 82.6% shrinks to only 81.5% in net terms. The gap of barely more than one point signals a near-absence of mobilizable public financial assets. Indonesia follows the same pattern: 42.2% gross, 40.7% net, a gap of about 1.5 points. Turkey, with 27.5% gross and 23.0% net, has a margin of only about 4.5 points.

The implications of these figures differ by country. For Turkey and Indonesia, the low debt stock limits risk, even without a cushion. For South Africa, the combination of high indebtedness and an absence of offsetting assets creates structural vulnerability. The country must finance the bulk of its debt on the markets, without being able to rely on public financial wealth.

The Intermediate Cases

Between these two poles, a group of countries shows moderate gaps. In the United Kingdom, France, and Mexico, the difference between gross and net debt hovers around 8 points. Saudi Arabia sits at a similar level, with 42.2% gross and 34.6% net. Italy shows a gap of about 9.4 points, Germany about 13 points (73.7% gross versus 60.7% net). Australia stands out with a differential of about 18.4 points, for gross debt of 49.1% and net debt of 30.7%. Brazil and the United States show more pronounced gaps, on the order of 25 to 27 points.

The European Bloc: Three Trajectories Under Strain

The three major continental European economies in the panel illustrate a particularly sharp internal divergence. Italy would retain the highest net debt ratio among the fifteen documented countries, at 126.7% of GDP. It would outpace Japan on this measure, even as it trails far behind in gross terms. With a thin asset cushion, the peninsula thus presents the most degraded net position in the sample.

France follows a comparable trajectory. Its projected gross debt of 120.7% and net debt of 112.6% place it among the most indebted advanced economies. In net terms, Paris would stand at the level of the United States (115.4%). Yet France has neither the status of a global reserve currency nor the market depth of Washington.

Germany appears in an entirely different category. With 73.7% gross debt and 60.7% net debt, Berlin would have a gap of about 47 points of gross debt with Rome and about 52 points of net debt. This gap is considerable for economies so commercially integrated. It suggests that public finance divergences reflect lasting differences in fiscal capacity and, in the background, in productive dynamism.

The United Kingdom, outside this continental trio, occupies an intermediate position: 102.6% gross, 94.5% net. It also carries one of the highest public spending weights among the countries for which this indicator is available, at 43.7% of GDP.

The United States and the Question of the State's Weight

Public spending is documented for only six countries in the available data. Yet it illuminates the reading of debt ratios. The United States would devote 38.1% of its GDP to public spending through 2031. That is significantly less than the United Kingdom (43.7%), but more than Russia (37.5%), Turkey (32.6%), South Africa (32.6%), or Saudi Arabia (25.0%).

Dividing gross debt by public spending yields an approximate indicator: the number of years of public spending represented by the debt stock. The United States stands out sharply here. Its gross debt would equal about 3.7 years of public spending. This ratio would be about 2.5 in South Africa, 2.3 in the United Kingdom, 1.7 in Saudi Arabia, and less than one year in Turkey (about 0.8) and Russia (about 0.8).

This simple calculation underscores an American characteristic: a state whose weight in the economy remains moderate, but which carries a very high debt stock. The projected net debt of 115.4% confirms that the asset cushion—real, at about 27 points of gap with gross debt—does not fundamentally alter the diagnosis. The United Kingdom presents the inverse configuration: a state more present in the economy, but a debt stock relative to spending that is substantially lower.

Emerging Markets: Divergence Within the Group Itself

Treating emerging economies as a homogeneous bloc would be an analytical error. The projected data reveal gaps as marked among them as between advanced countries.

China stands apart with projected gross debt of 126.8% of GDP. This level places it above France and just behind Italy, far from its emerging peers. Brazil follows with 106.5% gross, reduced to 81.1% net thanks to an asset cushion of about 25 points, one of the largest among the emerging countries in the panel. India, at 77.7%, occupies exactly the median position of the sample.

At the other extreme, several emerging economies would show very contained debt levels. Turkey would be the least indebted in the panel (27.5%), followed by Russia (29.1%), Indonesia and Saudi Arabia (both around 42.2%). Argentina would stand at 52.2% and Mexico at 63.6% gross, for 55.6% net.

For Saudi Arabia, a public spending ratio of 25.0% of GDP, the lowest of the six documented countries, adds to moderate debt. The whole paints a state with a light fiscal footprint. This profile theoretically leaves significant room for maneuver, provided the revenue base remains stable.

Productivity and Sustainability: Reading Beyond the Ratio

The productivity angle requires a methodological caveat. The available data include no direct indicator of labor or factor productivity. The analysis that follows therefore belongs to the economic reading framework, not empirical measurement. It remains indispensable, however, for interpreting the divergences observed.

The sustainability of public debt depends above all on the gap between the interest rate paid and the nominal growth rate of the economy. In the medium term, however, real growth rests largely on productivity gains. A ratio of 120% thus does not carry the same meaning in an economy whose productivity is advancing briskly and in one where it is stagnating. In the first case, growth of the denominator mechanically lightens the ratio. In the second, only fiscal consolidation can do so.

Viewed from this angle, the European divergence takes on particular relief. The gap of about 47 points of gross debt between Italy and Germany cannot be understood without the differences in long-term productive dynamism between the two countries. These differences condition both tax revenues and the capacity to absorb shocks. The question is comparable for France, whose projected net debt matches that of the United States without benefiting from the same structural advantages.

For economies with a large asset cushion, such as Canada, South Korea, or Japan, the logic is different. The accumulated public financial wealth offers a safety margin that mitigates dependence on productivity growth. For Japan, however, the level of net debt remains such that the growth trajectory remains a decisive parameter.

Among emerging economies, the challenge arises in terms of catch-up. Countries with moderate debt, such as Indonesia, Turkey, or Russia, have theoretical fiscal space to finance productive investment. For South Africa, whose gross debt would approach 83% without an asset cushion, the absence of vigorous productive dynamism would constitute the main risk factor. China, with gross indebtedness exceeding 126%, will need to obtain sufficient returns on its debt in terms of productivity gains to avoid self-sustaining accumulation.

The Signals to Watch

Several strategic lessons emerge from this forward-looking mapping. First, the gross debt ratio, often the only one highlighted in public debate, is a misleading indicator if not complemented by net debt. The cases of Canada and South Korea are the clearest demonstration, with respective gaps of about 93 and 50 points.

Second, the fiscal fracture does not follow the classic dividing line between advanced and emerging economies. China and Brazil rank among the most indebted. Germany and Australia (49.1% gross) remain clearly below the median, alongside several emerging markets.

Finally, the trajectories projected for 2031 pose a question that ratios alone cannot settle: that of future growth. For the most indebted states in net terms—Italy, Japan, the United States, and France, all beyond 110% of GDP—the capacity to durably revive productivity gains will condition the sustainability of their public finances. In the absence of comparable productivity data in the panel, this variable remains the blind spot of the analysis. Yet it is precisely this that will determine whether the current great fiscal divergence narrows or worsens over the coming decade.

This article was written with the assistance of artificial intelligence and verified by our editorial team.