The Point of No Return for Government Debt


Economic growth in the developed world is falling well short of the post-WWII experience, and there are identifiable causes.

Globalism — the opening of global trade — has caused developed economies to lose exports to lower-wage emerging nations and is but one factor. Another is the slowing of population and labor force growth (and, in some cases, both are shrinking). This contributes to the problem of slow economic growth as it restrains both aggregate supply and demand.

Furthermore, when populations stop growing, age-related government entitlements outpace economic growth as the age-profile of the population becomes top heavy with retirees. This, in turn, means taxes rise disproportionately on the backs of the relatively fewer workers, or the country — more realistically — resorts to debt financing.

Entitlements accelerate the accumulation of government debt now being piled on top of decades of Keynesian deficit spending that were an attempt to nudge higher growth rates.

It has long been a vague concern that government debt accumulation would be the ruination of an economy, and that sovereign defaults would occur as they have many times in that past. That issue is now front and center in both Europe and Japan, with the U.S. perhaps a decade behind.

Larger debt loads, however accumulated and whether from Keynesian economic stimulus, entitlements, war financing, or financial guarantees, cause tax rates to be higher than would be otherwise be necessary to pay yesterday’s incurred interest. It becomes a struggle for a government to merely pay interest without the possibility of retiring debt.

For example, in Japan, the debt-to-income ratio is a staggering 250 percent. This means that despite very low interest costs on government debt, 43 percent of tax proceeds are devoted to paying interest on its past debt.

Raising tax rates to pay debt service impacts the present as it becomes a negative incentive for investment spending. So past debt retards today’s economic growth.

The great danger of a high debt-to-income ratio is that it becomes self-reinforcing: We induce higher debt ratios not only via higher taxes to pay interest but also because the resulting economic slump unleashes Keynesian automatic stabilizers that have been built into an economy’s spend-and-tax reflexes.

As an economy’s growth rate slows, this kicks in income maintenance programs like unemployment support. At the same time, a slumping economy’s tax revenues erode more than in proportion to the slowdown in economic growth, which is a by-product of a progressive tax structure.

For example, in the first year of the Great Recession, U.S. government debt expanded by 15.8 percent while income declined by 2.8 percent, and together they ratcheted upward the debt-to-income ratio.

The economic slump produced by debt adds to government deficits resulting in yet more government debt and more taxes, which in turn reinforces the slump. The causation runs both ways: debt slows growth, and slow growth widens country deficits and accumulates debt.

What is being described is a self-reinforcing endogenous debt accumulation process in which the debt-to-income ratio rises until it can no longer be financed, resulting in a sovereign default.

The critical threshold when the self-reinforcing process of debt accumulation outpaces income growth has been aptly called the “bang point” by Reinhart and Rogoff (R & R). Their research, contained in their book “This Time Is Different,” shows that over many years, for many countries, that the threshold for debt to grow exponentially occurs when the debt-to-income ratio reaches approximately .9 — that is, when a country’s debt is 90 percent of its GDP.

R & R find that on average, for many countries, when that threshold level of the debt ratio has been reached, economic growth becomes retarded by 1 percent. In today’s world, much of Europe (and certainly Japan, too) is well above that point, and income growth has certainly declined and is barely positive.

For the U.S., at a debt-to-income ratio of 100 percent, economic growth is also being sucked into the endogenous web of debt in which, at best so far, GDP growth appears to be have been retarded by 1 percent annually.

The U. S. finds itself this year in a relatively weak cyclical upswing in which the growth of income and debt are both rising at approximately the same 2 percent rate so that the debt ratio is being maintained at the present time, but any slump in growth accelerates the debt ratio.

As a deterrent to debt accumulation, a heroic attempt is taking place in Japan and the U.S. to reduce the interest expense of government debt. Europe, via its European Central Bank (ECB), has recently engaged in a similar battle.

The debt service reduction is being described as quantitative easing (QE) and is being discussed and sold to the public as being a monetary policy to offer lower interest rates to stimulate interest rate-sensitive private spending. That is, low rates to stimulate growth.

Indeed, many of the central bankers are well trained Keynesians and they think that way, but to the political class, the central bankers are used as pawns to neutralize the government’s debt burden.

There is much debt service to be neutralized at current levels of debt, especially in Japan and Greece. What greatly complicates the problem of maintaining debt service with a high debt ratio is that the government bond market, when it senses that the debt problem is getting out of control, will only finance the government’s debt with elevated interest rates that imbed a sovereign risk premium.

To get a sense for a country’s interest cost exposure to sovereign default pricing, take a simple example of a debt-to-income ratio of 1 and an (unrealistic) interest expense that averages 1 percent on all government debt issues. In this case, taxation would only need to capture 1 percent of a nation’s GDP to service country debt. This expense is manageable.

But to be more realistic, sovereign bond yields on 10-year debt maturities are shown below for several different recent European sovereign bond market eras.

Prior to the common currency that arrived in 1999, when the Euro countries were on their own (in the sense of no support from by each other or by a central bank), sovereign yields were priced to reflect sovereign risk.

At the start of the common currency in 1999, the sovereign rates came together at Germany’s base rate during the honeymoon of the Euro zone when it was presumed that the stronger countries would come to the aid of the weaker if need be — and if not, there was a central bank to provide assistance. Also debt control was a pre-requisite to be a member of the Euro zone.

This presumption of aid to the weak became questioned after the financial crisis, and there was a weakening of country debt control. This relevant era began in 2008, at which time the market priced country vulnerability with little or no help from neighbors or by the central bank because “monetary finance” (or central bank financing of governments) was still taboo.

That environment reveals clearly how hard markets will punish sovereigns with debt problems. High single digit sovereign yields existed, and Greece, which was headed for its first default, experienced a 30 percent market cost of finance for 10-year maturities.

In this case, for a country with debt equal to 250 percent of annual GDP, and if its sovereign average cost of funding for all maturities was merely 10 percent, that country would need to capture fully 25 percent of GDP to pay interest alone without any of the other costs of government being covered. There would be debt cost of that magnitude likely for both Greece and Japan.

That is the process by which default is brought on when the debt-to-income ratio reaches the bang point. It might take a few years, but the process grinds on until the income lost attempting to tax and service the debt becomes impossible to bear.

So, in a last ditch effort to avoid default, the central bank intervenes with quantitative easing to reduce interest rates paid by sovereigns. QE is in process in Europe, but as things currently stand, Greece’s sovereign debt is not investment-grade and, hence, is not eligible for purchase by the ECB unless the rules are bent or the rating is changed which is a likely response in the pragmatic business of saving the sovereign, otherwise known as “Whatever it takes.”

Alternatively, Greece would need to drop out of the currency union, likely default on its debt in whole or in part, and go back to its own currency from which they can continue to play the money game to depress interest expense. In the case of Japan, the pretense continues, but they are past the bang point and — short of some new exogenous source of demand for their products revealing itself — they are sinking deeply into the morass of debt and debt service.

But will central bank QE really contain the debt service problem? The answer has to be no because the side effects of the debt solution becomes its own problem.

With such low investment returns in-county, capital flees to higher-yielding locations and, without capital, there is no financing of private investment and the real physical capital stock becomes a relic of yesterday. This erodes income and raises the debt-to-income ratio further.

Once having reached the bang point, QE is too late and counterproductive.


The views expressed are those of the author and not necessarily The University of Texas at Austin.

About The Author

Lew Spellman

Professor, Department of Finance, McCombs School of Business, The University of Texas at Austin

Lewis Spellman received his BBA and MBA from the University of Michigan and his MA and Ph.D. from Stanford University. His research interests include...

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