The market price of trills would fluctuate, reflecting the changing prospects for future G.D.P. growth, just as the market price of stocks reflects the changing prospects for future earnings growth. There is no complexity here. It is all plain-vanilla financing, though unconventional by today’s standards.

There are indications that officials in China are starting to worry about threats to their huge investment in United States debt from a possible outbreak of high inflation. The trills, tied to nominal G.D.P., would protect them. Right now TIPS, or Treasury Inflation-Protected Securities, are offering disappointingly low yields, which may have to be raised to attract more investment. Trills, even at an ultralow dividend yield, would seem more exciting as an inflation-protected prospect, because they represent a share in future economic growth.

The United States government is highly unlikely to default on its debt, but even this remote possibility would be virtually eliminated by trills, because the government’s dividend burden would automatically decline in tough times, when G.D.P. declined.

The final statement of the Group of 20 economic meeting in Pittsburgh in September pledged to “establish a pattern of growth across countries that is more sustainable and balanced, and reduce development imbalances.” These imbalances  exemplified by the massive Chinese holdings of United States government debt  might not be so worrisome if the investments were financed better.

In fact, issuing shares in G.D.P. might even be viewed as a policy that systematically rectifies a wide array of imbalances in capital flows. People who expect strong economic growth in a country would bid up the price of a claim on its G.D.P., creating a cheap source of funding for the issuing government. So a country with good investment prospects gets the resources at a low current cost. There would be no need for central bank machinations to try to correct global imbalances.

We already have international equity markets that allow international investments in private firms within countries. But these do not represent the entire economy. Corporate stocks represent implicit claims on after-tax corporate profits, which typically amount to no more than 10 percent of G.D.P. Moreover, after-tax corporate profits are a much more slippery concept than G.D.P., affected as they are by many domestic policies, including taxes, government involvement in labor disputes and even government bailouts  as we now know very well.