The FTPL version of the Neo-Fisherian proposition

Probably for macroeconomists

The Neo-Fisherian doctrine is the idea that a permanent increase in a flat nominal interest rate path will (eventually) raise the inflation rate. It is then suggested that current below target inflation is a consequence of fixing rates at their lower bound, and rates should be raised to increase inflation. David Andolfatto says there are two versions of this doctrine. The first he associates with the work of Stephanie Schmitt-Grohe and Martin Uribe, which I discussed here. He like me is not sold on this interpretation, for I think much the same reason. (There is a closely related discussion of the Neo-Fisherian doctrine by John Cochrane, which I will refer to in a subsequent post on Woodford’s recent idea of reflective equilibrium.) But he favours a different interpretation, based on the Fiscal Theory of the Price Level (FTPL).

Let me first briefly outline my own interpretation of the FTPL. This looks at the possibility of a fiscal regime where there is no attempt to stabilise debt. Government spending and taxes are set independently of the level or sustainability of government debt. The conventional and quite natural response to the possibility of that regime is to say it is unstable. But there is another possibility, which is that monetary policy stabilises debt. Again a natural response would be to say that such a monetary policy regime is bound to be inconsistent with hitting an inflation target in the long run, but that is incorrect.

A simple example is a model without sticky prices where bonds are denominated in nominal terms, and a monetary policy that involves a constant nominal interest rate. A constant nominal interest rate policy is normally thought to be indeterminate because the price level is not pinned down, even though the expected level of inflation is. In the FTPL, the price level is pinned down by the need for the government budget to balance at arbitrary and constant levels for taxes and spending.

The idea still works even with sticky prices and indexed debt, as my EJ paper with Tatiana Kirsanova shows. Here the budget is balanced, after a positive shock to debt say, by a period of above target inflation which reduces real government debt through lower real interest rates. This raises a somewhat pedantic point about David’s post. I’m not sure the path he shows for inflation, with no inflation surprises and no period of lower real rates, would be sufficient to stabilise the government’s budget constraint. Unless I have missed something, a period of higher inflation is required to do this. 

However I have a much more serious problem with this FTPL interpretation in the current environment. The belief that people would need to have for the FTPL to be relevant - that the government would not react to higher deficits by reducing government spending or raising taxes - does not seem to be credible, given that austerity is all about them doing exactly this despite being in a recession. As a result, I still find the Neo-Fisherian proposition, with either interpretation, somewhat unrealistic.