This paper investigates purchasing-power parity (PPP) since the late nineteenth century. I collected data for a group of twenty countries over 100 years, a larger historical panel of annual data than has ever been studied. The evidence for long-run PPP is favorable using recent multivariate and univariate tests of higher power. Residual variance analysis shows that episodes of floating exchange rates have generally been associated with larger deviations from PPP, as expected; this result is not attributable to significantly greater persistence (longer half-lives) of deviations in such regimes, but is due to the larger shocks to the real exchange rate process in such episodes. In the course of the twentieth century, there was relatively little change in the capacity of international market integration to smooth out real exchange rate shocks. Instead, changes in the size of shocks depended on the political economy of monetary and exchange rate regime choice under the constraints imposed by the trilemma.

We offer a new explanation as to why international trade is so volatile in response to economic shocks. Our approach combines the uncertainty shock idea of Bloom (2009) with a model of international trade, extending the idea to the open economy. Firms import intermediate inputs from home or foreign suppliers, but with higher costs in the latter case. Due to fixed costs of ordering firms hold an inventory of intermediates. We show that in response to an uncertainty shock firms optimally adjust their inventory policy by cutting their orders of foreign intermediates disproportionately strongly. In the aggregate, this response leads to a bigger contraction in international trade flows than in domestic economic activity. We confront the model with newly-compiled monthly aggregate U.S. import data and industrial production data going back to 1962, and also with disaggregated data back to 1989. Our results suggest a tight link between uncertainty and the cyclical behavior of international trade.

According to the Washington Consensus, developing countries' growth would benefit from reductions in barriers to trade. However, the empirical basis for judging trade reforms is weak. Econometrics are mostly ad hoc, results are typically not judged against models, policies are poorly measured, and most studies are based on pre-1990 experience. We address these concerns by employing a model with capital and intermediate goods, compiling new disaggregated tariff measures, and employing treatment and control regression analysis with differences-in-differences. We find that a specific treatment, liberalizing tariffs on imported capital and intermediate goods, led to faster growth, consistent with the model.

A major question in the literature on the classical gold standard concerns the efficiency of international arbitrage. Authors have examined efficiency by looking at the spread of the gold points, gold point violations, the flow of gold, or by tests of various asset market criteria, including speculative efficiency and interest arbitrage. These studies have suffered from many limitations, both methodological and empirical. We offer a new methodology for measuring market integration based on nonlinear theoretical models and threshold autoregressions. We also compile a new, highfrequency series of continuous daily data from 1879 to 1913. We can derive reasonable econometric estimates of the implied gold points and price dynamics. The changes in these measures over time provide an insight into the evolution of market integration.

Conventional wisdom in economic history suggests that conflict between countries can be enormously disruptive of economic activity, especially international trade. We study the effects of war on bilateral trade with available data extending back to 1870. Using the gravity model, we estimate the contemporaneous and lagged effects of wars on the trade of belligerent nations and neutrals, controlling for other determinants of trade, as well as the possible effects of reverse causality. We find large and persistent impacts of wars on trade, national income, and global economic welfare. We also conduct a general equilibrium comparative statics exercise that indicates costs associated with lost trade might be at least as large as the conventionally measured direct costs of war, such as lost human capital, as illustrated by case studies of World Wars I and II.

The exchange-rate regime is often seen as constrained by the monetary policy trilemma, which imposes a stark tradeoff among exchange stability, monetary independence, and capital market openness. Yet the trilemma has not gone without challenge. Some (e.g., Others (e.g., This paper studies the coherence of international interest rates over more than 130 years. The constraints implied by the trilemma are largely borne out by history.

We document that the real effects of monetary shocks last for over a decade. Our approach relies on (1) identification of exogenous and non-systematic monetary shocks using the trilemma of international finance; (2) merged data from two new international historical cross-country databases; and (3) econometric methods robust to long-horizon inconsistent estimates. Notably, the capital stock and total factor productivity (TFP) exhibit greater hysteresis than labor. When we allow for asymmetry, we find these effects with tightening shocks, but not with loosening shocks. When extending the horizon of the responses reported in several recent studies that use alternative monetary shocks, we find similarly persistent real effects, thus supporting our main findings.

What are the medium- to long-term effects of pandemics? Do they differ from other economic disasters? We study major pandemics using rates of return on assets stretching back to the fourteenth century. Significant macroeconomic after-effects of pandemics persist for decades, with rates of return substantially depressed. The responses are in stark contrast to what happens after wars. Our findings also accord with wage and output responses, using more limited data, and are consistent with the neoclassical growth model: capital is destroyed in wars but not in pandemics; pandemics instead may induce more labor scarcity or more precautionary savings, or both.