Real Exchange Rate Targeting and Macroeconomic Instability

Using an optimizing model of a small open economy, this paper studies the macroeconomic effects of PPP rules whereby the government increases the devaluation rate when the real exchange rate defined as the price of tradables in terms of nontradables is below its long-run level and reduces the devaluation rate when the real exchange rate is above its long-run level. The paper shows that the mere existence of such a rule can generate aggregate fluctuations due to self-fulfilling revisions in expectations. The result is shown to obtain in both flexible- and sticky-price environments.

A Fiscal Theory of Sovereign Risk

This paper presents a fiscal theory of sovereign risk and default. Under certain monetary-fiscal regimes, the risk of default, and thus the emergence of sovereign risk premia, are inevitable. The paper characterizes the equilibrium processes of the sovereign risk premium and the default rate under a number of alternative monetary policy arrangements. Under some of the policy environments considered, the expected default rate and the sovereign risk premium are zero although the government defaults regularly. Under other monetary regimes the default rate and the sovereign risk premium are serially correlated and therefore forecastable. Environments are characterized under which delaying default is counterproductive.

On Overborrowing

This paper characterizes the equilibrium dynamics in an economy facing an aggregate debt ceiling. This borrowing limit is intended to capture an environment in which foreign investors base their lending decisions predominantly upon macro indicators. Individual agents do not internalize the borrowing constraint. Instead, a country interest-rate premium emerges to clear the financial market. The implied equilibrium dynamics are compared to those arising from a model in which the debt ceiling is imposed at the level of each individual agent. The central finding of the paper is that the economy with the aggregate borrowing limit does not generate higher levels of debt than the economy with the individual borrowing limit. That is, there is no overborrowing in equilibrium.

Anticipated Ramsey Reforms and the Uniform Taxation Principle: the Role of International Financial Markets

This paper studies the role of asset-market completeness for the properties of optimal policy. A suitable framework for this purpose is the small open economy with complete international asset markets. For in this environment changes in policy represent country-specific risk diversifiable in world markets. Our main finding is that the fundamental public finance principle whereby when taxes on all final goods are available, it is optimal to tax final goods uniformly fails to obtain. In general, uniform taxation is optimal because it amounts to a nondistorting tax on fixed factors of production. In the open economy this principle fails because when households can insure against the risk of a policy reform, initial private asset holdings are contingent on actual policy and thus no longer represent an inelastically supplied source of income. Two further differences between optimal policy in the closed and open economies with complete markets are: (a) In the open economy, optimal consumption and income tax rates are unchanged in response to government purchases shocks. By contrast, in the closed economy tax rates do respond to innovations in public spending. (b) In the open economy, the Friedman rule is optimal only if the Ramsey planner has access to consumption taxes. In the absence of consumption taxes, deviations from the Friedman rule are large. On the other hand, in the closed economy, the availability of either consumption or income taxes suffices to render the Friedman rule optimal.

Optimal Inflation Stabilization in a Medium-Scale Macroeconomic Model

This paper characterizes Ramsey-optimal monetary policy in a medium-scale macroeconomic model that has been estimated to fit well postwar U.S.\ business cycles. We find that mild deflation is Ramsey optimal in the long run. However, the optimal inflation rate appears to be highly sensitive to the assumed degree of price stickiness. Within the window of available estimates of price stickiness (between 2 and 5 quarters) the optimal rate of inflation ranges from -4.2 percent per year (close to the Friedman rule) to -0.4 percent per year (close to price stability). This sensitivity disappears when one assumes that lump-sum taxes are unavailable and fiscal instruments take the form of distortionary income taxes. In this case, mild deflation emerges as a robust Ramsey prediction. In light of the finding that the Ramsey-optimal inflation rate is negative, it is puzzling that most inflation-targeting countries pursue positive inflation goals. We show that the zero bound on the nominal interest rate, which is often cited as a rationale for setting positive inflation targets, is of no quantitative relevance in the present model. Finally, the paper characterizes operational interest-rate feedback rules that best implement Ramsey-optimal stabilization policy. We find that the optimal interest-rate rule is active in price and wage inflation, mute in output growth, and moderately inertial. This rule achieves virtually the same level of welfare as the Ramsey optimal policy.

Optimal Fiscal and Monetary Policy Under Imperfect Competition

This paper studies optimal fiscal and monetary policy under imperfect competition in a stochastic, flexible-price, production economy without capital. It shows analytically that in this economy the nominal interest rate acts as an indirect tax on monopoly profits. Unless the social planner has access to a direct 100 percent tax on profits, he will always find it optimal to deviate from the Friedman rule by setting a positive and time-varying nominal interest rate. The dynamic properties of the Ramsey allocation are characterized numerically. As in the perfectly competitive case, the labor income tax is remarkably smooth, whereas inflation is highly volatile and serially uncorrelated. An exact numerical solution method to the Ramsey conditions is proposed.

The Business Cycles of Balance-of-Payment Crises: A Revision of Mundellan Framework

In his seminal 1960 article Robert Mundell proposed a model of balance-of-payments crises in which confidence in the continuation of a currency peg depended on the observed holdings of central bank foreign reserves. We examine the implications of a reformulation of this view from the perspective of an equilibrium business cycle model in which the probability of devaluation is an endogenous variable conditioned on foreign reserves. The model explains some business cycle regularities of exchange-rate-based stabilizations while also producing devaluation probabilities that capture some features of devaluation probabilities estimated in the data. The analysis aims to explain both the real effects and the collapse of temporary fixed-exchange-rate regimes in an unified framework, and provides an economic interpretation for the evidence that foreign reserves are a robust leading indicator of currency crises.

Devaluation Risk and the Syndrome of Exchange-Rate-Based Stabilizations

This paper shows that the risk of devaluation can be an important factor accounting for the stylized facts of exchange-rate-based stabilizations. This conclusion follows from studying the quantitative implications of a two-sector equilibrium business cycle model of a small open economy calibrated to Mexico's 1987-1994 stabilization plan. In the model a time-variant interest rate differential that acts as a stochastic tax on money demand, labor supply, investment, and saving. Under incomplete markets, this tax induces endogenous state-contingent wealth effects via fiscal adjustment and suboptimal investment. Devaluation risk entails large welfare costs in this environment.

Optimal Simple and Implementable Monetary and Fiscal Rules

The goal of this paper is to compute optimal monetary and fiscal policy rules in a real business cycle model augmented with sticky prices, a demand for money, taxation, and stochastic government consumption. We consider simple policy rules whereby the nominal interest rate is set as a function of output and inflation, and taxes are set as a function of total government liabilities. We require policy to be implementable in the sense that it guarantees uniqueness of equilibrium. We do away with a number of empirically unrealistic assumptions typically maintained in the related literature that are used to justify the computation of welfare using linear methods. Instead, we implement a second-order accurate solution to the model. Our main findings are: First, the size of the inflation coefficient in the interest-rate rule plays a minor role for welfare. It matters only insofar as it affects the determinacy of equilibrium. Second, optimal monetary policy features a muted response to output. More importantly, interest rate rules that feature a positive response of the nominal interest rate to output can lead to significant welfare losses. Third, the optimal fiscal policy is passive. However, the welfare losses associated with the adoption of an active fiscal stance are negligible.

Backward-Looking Interest-Rate Rules, Interest-Rate Smoothing, and Macroeconomic Instability

The existing literature on the stabilizing properties of interest-rate feedback rules has stressed the perils of linking interest rates to forecasts of future inflation. Such rules have been found to give rise to aggregate fluctuations due to self-fulfilling expectations. In response to this concern literature has focused on the stabilizing properties of interest-rate rules whereby the central bank responds to a measure of past inflation. The consensus view that has emerged is that backward-looking rules contribute to protecting the economy from embarking on expectations-driven fluctuations. A common characteristic of the existing studies that arrive at this conclusion is their focus on local analysis. The contribution of this paper is to conduct a more global analysis. We find that backward-looking interest-rate feedback rules do not guarantee uniqueness of equilibrium. We present examples in which for plausible parameterizations attracting equilibrium cycles exist. The paper also contributes to the quest for policy rules that guarantee macroeconomic stability globally. Our analysis indicates that policy rules whereby the interest rate is set as a function of the past interest rate and current inflation are likely to ensure global stability provided that the coefficient on lagged interest rates is greater than unity.