For those that haven't yet had the opportunity to read Steve Keen, an economist out of Australia who has had some very insightful posts in the past (February's The Roving Cavaliers of Credit is a great 'out of the box' piece that I've reread multiple times), I recommend his latest piece 4 Years Calling the GFC (i.e. the Global Financial Crisis). He noticed that Australia and the United States have been able to service a growing level of debt (which has driven a significant portion of past economic growth) due to interest rates that have moved lower and lower, resulting in servicing costs that have stayed relatively flat.
The issue is what happens when you hit the zero bound and can no longer lower rates (or when the marginal buyer is not willing to accept those lower and lower levels). The best case is lower growth as those debt levels are worked off / inflated away gradually. A worst case is when those levels reach an unsustainable level and default is brought into question (the U.S. really can't default, but bringing out the printing press just to make payments would result in a situation just as bad in my opinion).
The level Steve Keen chose to look at to see just how much debt the U.S. has piled up was debt as a level of GDP. Why?
In dynamic terms, the ratio of debt to GDP tells you how many years it would take to reduce debt to zero if all income was devoted to debt repayment. That is an extremely valid indicator of the degree of financial stress a society (or an individual) is under.That makes sense, but I thought debt levels relative to the actual receipts brought in by the government to service that actual debt would be interesting / instructive. As a result we have the below chart, which is marked by a collapse of tax revenue at its most recent point, but the result is frightening none-the-less.
Sources: Government debt outstanding (per Treasury Direct) divided by the twelve month rolling level of receipts (per the Treasury )