I examine how money and trend inflation shaped US macroeconomic dynamics during the Great Inflation. I develop a business cycle model with positive trend inflation where money is allowed (but not required) to play a role in determining the equilibrium values of inflation and output through non-separable utility, adjustment costs for holding real balances, and the monetary policy reaction function. The Taylor principle changes in this environment. Targeting money guarantees price determinacy even with trend inflation, but these results are sensitive to the inclusion of non-separability and portfolio adjustment costs. The framework is combined with Greenbook data that detect the role of money in the policy reaction function. The response to money was likely not sufficiently strong to complement the reaction to inflation and counteract the high trend inflation observed during the pre-Volcker period, which most likely led to price indeterminacy.

This paper studies how model uncertainty influences economic fluctuation when trend inflation is high. We introduce Hansen and Sargent’s [(2008) Robustness, Princeton University Press] robust control techniques into a New Keynesian model with non-zero trend inflation. We reveal the following three points. First, we find that robust monetary policy responds more aggressively. This aggressiveness increases with trend inflation. Second, as the trend inflation rises, the response of macroeconomic variables is larger under robust policy. Third, stronger robustness tends to lead to indeterminate equilibrium as trend inflation increases. Consequently, the economy might be volatile when trend inflation is high due to robustness from the view of both variance and determinacy. We interpret the results as indicating that the model uncertainty might be the one of the factors causing large macroeconomic fluctuations when trend inflation is high.

A wage setting process defined in terms of wage per hour is the key factor for obtaining negative optimal trend inflation in a closed economy. However, this inflation will be zero if the process is established on the wage per unit of human capital. The origin of both results is a dynamic mechanism that, with some differences, makes possible the attainment of a situation equivalent to wage flexibility. Finally, while the effect of trend inflation on the long-run growth rate is tiny in the first case, it is much more important in the second, highlighting the relevance of this approach.

I use a two-country dynamic stochastic general equilibrium (DSGE) model with a nonzero steady-state inflation to study monetary policy in transition economies. In particular, my analysis focuses on whether inflation targeting is based on a consumer price index (CPI) or its producer counterpart, producer price index (PPI). This issue is specifically relevant for transition economies as they might be subject to Balassa–Samuelson effects arising from trading in international markets. Under these circumstances, domestic inflation is possibly higher than imported inflation, hence targeting PPI inflation may prove more effective in influencing domestic macroeconomic variables than targeting CPI inflation. Using a Bayesian methodology, I find that the central banks of three Eastern European countries (namely, the Czech Republic, Hungary, and Poland) are likely to target PPI inflation rather than CPI inflation. This result is in line with the theoretical predictions in the literature, and is robust across several Taylor-type rules.

In sticky price models based on micro evidence that each period a fraction of prices are kept unchanged, recent studies reach the qualitatively equivalent conclusion that higher trend inflation is a more serious source of indeterminacy of rational expectations equilibrium, regardless of whether labor is firm-specific or homogeneous. This paper shows that the model with firm-specific labor is more susceptible to indeterminacy induced by high trend inflation than the model with homogeneous labor, because these two different specifications of labor lead to distinct representations of inflation dynamics. In addition, the model with firm-specific labor is more susceptible to expectational instability of the equilibrium caused by high trend inflation.

This paper offers a reinterpretation of the Fed's time-varying implicit inflation target, based on two considerations. The first is that the need to alleviate the burden of distortionary taxation may justify the choice of a positive inflation rate. The second is based on compelling evidence that the degree of price and wage indexation falls with trend inflation. In fact, we find that a proper characterization of the joint evolution of fiscal variables and nominal rigidities has a strong impact on the Ramsey optimal policies, implying optimal inflation dynamics that are consistent with the observed evolution of U.S. trend inflation. By contrast, tax policies have been too lax, especially at the time of the controversial Bush tax cuts.

We investigate the importance of trend inflation and the real-activity gap in explaining inflation in G7 countries since 1960. Our analysis is based on a bivariate unobserved components model of inflation and unemployment in which inflation is decomposed into a stochastic trend and a transitory component. As in recent implementations of the New Keynesian Phillips Curve, it is the transitory component of inflation, or “inflation gap,” that is driven by the real-activity gap, which we measure as the deviation of unemployment from its natural rate. We find that both trend inflation and the inflation gap have been consistent and substantial determinants of inflation at business cycle horizons for all G7 countries since 1960. Also, the real-activity gap explains a large fraction of the variation in the inflation gap for each country. These results provide empirical support for the New Keynesian Phillips Curve augmented with trend inflation.

This paper estimates Taylor rules featuring instabilities in policy parameters and switches in policy shocks’ volatility for the post-World War II (WWII) U.S. economy. We contrast a rule embedding a fixed-inflation target with another featuring trend inflation, i.e., a time-varying inflation target. The rule embedding trend inflation turns out to be (a) empirically superior according to a marginal likelihood-based comparison and (b) more able to pin down some relevant episodes of the post-WWII U.S. monetary policy history. Estimates conducted with Greenbook data confirm the empirical superiority of the rule featuring a time-varying inflation target. A comparison with recently published estimates of trend inflation is also conducted.

This study examines the expectational stability of rational expectations equilibria (REE) under alternative Taylor rules when trend inflation is nonzero. We find that when trend inflation is high, the REE is likely to be expectationally unstable. This result holds true regardless of the nature of the data (such as contemporaneous, forecast, or lagged data) introduced in the Taylor rule. Our results suggest that high macroeconomic volatility during the period of high trend inflation can be explained well by introducing the concept of expectational stability.

This paper proposes the use of wavelet methods to estimate U.S. core inflation. It explains wavelet methods and suggests that they are ideally suited to this task. Comparisons are made with traditional Consumer Price Index–based and regression-based measures for their performance in following trend inflation and predicting future inflation. Results suggest that wavelet-based measures perform better, and sometimes much better, than the traditional approaches. These results suggest that wavelet methods are a promising avenue for future research on core inflation.