The answer to the question in the title is: A lot. In this essay, I argue that the history of macroeconomics during the 20th century can be divided in three epochs: Pre 1940. A period of exploration, where macroeconomics was not macroeconomics yet, but monetary theory on one side, business cycle...

This paper starts from two sets of facts about Continental Europe.The first is the steady increase in unemployment since the early 1970s. The second is the evolution of the capital share, an initial decline in the 1970s, followed by a much larger increase since the mid-1980s. The paper then...

Current account imbalances have steadily increased in rich countries over the last 20 years. While the U.S. current account deficit dominates the numbers and the news, other countries, especially within the Euro area, are also running large deficits. These deficits are different from the Latin...

In the 1970s, European unemployment started increasing. It increased further in the 1980s, to reach a plateau in the 1990s. It is still high today, although the average unemployment rate hides a high degree of heterogeneity across countries. The focus of researchers and policy makers was...

A standard proposition in open-economy macroeconomics is that a central-bank-engineered increase in the real interest rate makes domestic government debt more attractive and leads to a real appreciation. If, however, the increase in the real interest rate also increases the probability of...

After three years of near stagnation, the mood in Europe is definitely gloomy. Many doubt that the European model has a future. In this paper, I argue that things are not so bad, and there is room for optimism. Over the last thirty years, productivity growth has been much higher in Europe than...

The strong monetary policy actions undertaken by advanced economies' central banks have led to complaints of "currency wars" by some emerging market economies, and to widespread demands for more macroeconomic policy coordination. This paper revisits these issues. It concludes that, while...

This paper has a simple goal, that of understanding the joint behaviorof prices and quantities in a particular market. More precisely, it examines whether we can find decision problems for suppliers and buyers, together with a market equilibrium structure, which are consistent with the observed...

We characterize the macroeconomic performance of a set of industrialized economies in the aftermath of the oil price shocks of the 1970s and of the last decade, focusing on the differences across episodes. We examine four different hypotheses for the mild effects on inflation and economic...

This paper analyzes the issue of persistent high unemployment. It focuses on two channels of persistence. The first is capital accumulation. The paper analyzes investment decisions under imperfect competition, focusing in particular on the effects of demand and cost shocks on investment, capital...