The golden rule of public debt

23 Jan, 2017 at 16:57 | Posted in Economics | 2 Comments

Nation states borrow to provide public capital: For example, rail networks, road systems, airports and bridges. These are examples of large expenditure items that are more efficiently provided by government than by private companies.

The benefits of public capital expenditures are enjoyed not only by the current generation of people, who must sacrifice consumption to pay for them, but also by future generations who will travel on the rail networks, drive on the roads, fly to and from the airports and drive over the bridges that were built by previous generations. Interest on the government debt is a payment from current taxpayers, who enjoy the fruits of public capital, to past generations, who sacrificed consumption to provide that capital.

To maintain the roads, railways, airports and bridges, the government must continue to invest in public infrastructure. And public investment should be financed by borrowing, not from current tax revenues …

The debt raised by a private sector company should be strictly less than the value of assets, broadly defined. That principle does not apply to a nation state. Even if government provided no capital services, the value of its assets or liabilities should not be zero except by chance.

National treasuries have the power to transfer resources from one generation to another. By buying and selling assets in the private markets, government creates opportunities for those of us alive today to transfer resources to or from those who are yet to be born. If government issues less debt than the value of public capital, there will be an implicit transfer from current to future generations. If it owns more debt, the implicit transfer is in the other direction.

The optimal value of debt, relative to public capital, is a political decision. Public economics suggests that the welfare of the average citizen will be greatest when the growth rate is equal to the interest rate. Economists call that principle the golden rule. Democratic societies may, or may not, choose to follow the golden rule. Whatever principle the government does choose to fund its expenditure, the optimal value of public sector borrowing will not be zero, except by chance.

Roger Farmer

Today there seems to be a rather widespread consensus of public debt being acceptable as long as it doesn’t increase too much and too fast. If the public debt-GDP ratio becomes higher than X % the likelihood of debt crisis and/or lower growth increases.

But in discussing within which margins public debt is feasible, the focus, however, is solely on the upper limit of indebtedness, and very few asks the question if maybe there is also a problem if public debt becomes too low.

The government’s ability to conduct an ‘optimal’ public debt policy may be negatively affected if public debt becomes too small. To guarantee a well-functioning secondary market in bonds it is essential that the government has access to a functioning market. If turnover and liquidity in the secondary market becomes too small, increased volatility and uncertainty will in the long run lead to an increase in borrowing costs. Ultimately there’s even a risk that market makers would disappear, leaving bond market trading to be operated solely through brokered deals. As a kind of precautionary measure against this eventuality it may be argued — especially in times of financial turmoil and crises — that it is necessary to increase government borrowing and debt to ensure — in a longer run — good borrowing preparedness and a sustained (government) bond market.

The question if public debt is good and that we may actually have to little of it is one of our time’s biggest questions. Giving the wrong answer to it will be costly.

One of the most effective ways of clearing up this most serious of all semantic confusions is to point out that private debt differs from national debt in being external. It is owed by one person to others. That is what makes it burdensome … But this does not hold for national debt which is owed by the nation to citizens of the same nation. There is no external creditor. We owe it to ourselves.

A variant of the false analogy is the declaration that national debt puts an unfair burden on our children, who are thereby made to pay for our extravagances. Very few economists need to be reminded that if our children or grandchildren repay some of the national debt these payments will be made to our children or grandchildren and to nobody else. Taking them altogether they will no more be impoverished by making the repayments than they will be enriched by receiving them.

Abba Lerner The Burden of the National Debt (1948)