In the United States and a few European countries, inventory behavior is mainly the outcome of demand shocks: a standard buffer-stock model best characterizes these economies. But most European countries are described by a modified buffer-stock model where supply shocks dominate. In contrast to the United States, inventories boost growth with a one-year lag in Europe. Moreover, inventories provide limited information to improve growth forecasts particularly when a modified buffer-stock model characterizes inventory behavior.

This book introduces a new approach in the field of macroeconomic inventory studies: the use of multivariate statistics to evaluate long-term characteristics of inventory investments in developed countries. By analyzing a 44-year period series of annual inventory change in percentage of GDP in a set of OECD countries, disclosing their relationship to growth, industry structure and alternative uses of GDP (fixed capital investments, foreign trade and consumption), it fills a gap in the economic literature. It is generally accepted that inventories play an important role in all levels of the economy. However, while there is extensive literature on micro- (and even item-) level inventory problems, macroeconomic inventory studies are scarce. Both the long-term processes of inventory formation and their correlation with other macroeconomic factors provide interesting conclusions about economic changes and policies in our immediate past, and present important insights for the future.

The September 2011 edition of the World Economic Outlook assesses the prospects for the global economy, which is now in a dangerous new phase. Global activity has weakened and become more uneven, confidence has fallen sharply recently, and downside risks are growing. Against a backdrop of unresolved structural fragilities, a barrage of shocks hit the international economy this year, including the devastating Japanese earthquake and tsunami, unrest in some oil-producing countries, and the major financial turbulence in the euro area. Two of the forces now shaping the global economy are high and rising commodity prices and the need for many economies to address large budget deficits. Chapter 3 examines the inflationary effects of commodity price movements and the appropriate monetary policy response. Chapter 4 explores the implications of efforts by advanced economies to restore fiscal sustainability and by emerging and developing economies to tighten fiscal policy to rebuild fiscal policy room and in some cases to restrain overheating pressures.

The Q&A in this issue features seven questions about emerging markets and the financial crisis (by Ayhan Kose); the research summaries are "Tax Revenue Response to the Business Cycle" (by Cemile Sancak, Ricardo Velloso, and Jing Xing) and "Banking Crisis Resolution: Was this Time Different?" (by Luc Laeven and Fabian Valencia). The issue also lists the contents of the second issue of the IMF Economic Review, Volume 58 Number 2; visiting scholars at the IMF during October-December 2010; and recent IMF Working Papers and Staff Position Notes.

In recent decades the American economy has experienced the worst peace-time inflation in its history and the highest unemployment rate since the Great Depression. These circumstances have prompted renewed interest in the concept of business cycles, which Joseph Schumpeter suggested are "like the beat of the heart, of the essence of the organism that displays them." In The American Business Cycle, some of the most prominent macroeconomics in the United States focuses on the questions, To what extent are business cycles propelled by external shocks? How have post-1946 cycles differed from earlier cycles? And, what are the major factors that contribute to business cycles? They extend their investigation in some areas as far back as 1875 to afford a deeper understanding of both economic history and the most recent economic fluctuations. Seven papers address specific aspects of economic activity: consumption, investment, inventory change, fiscal policy, monetary behavior, open economy, and the labor market. Five papers focus on aggregate economic activity. In a number of cases, the papers present findings that challenge widely accepted models and assumptions. In addition to its substantive findings, The American Business Cycle includes an appendix containing both the first published history of the NBER business-cycle dating chronology and many previously unpublished historical data series.

This paper focuses on the sluggish growth of world trade relative to income growth in recent years. The analysis uses an empirical strategy based on an error correction model to assess whether the global trade slowdown is structural or cyclical. An estimate of the relationship between trade and income in the past four decades reveals that the long-term trade elasticity rose sharply in the 1990s, but declined significantly in the 2000s even before the global financial crisis. These results suggest that trade is growing slowly not only because of slow growth of Gross Domestic Product (GDP), but also because of a structural change in the trade-GDP relationship in recent years. The available evidence suggests that the explanation may lie in the slowing pace of international vertical specialization rather than increasing protection or the changing composition of trade and GDP.

This edition of the World Economic Outlook explores how a dramatic escalation of the financial crisis in September 2008 provoked an unprecedented contraction of activity and trade, despite active policy responses. It presents economic projections for 2009 and 2010, and also looks beyond the current crisis, considering factors that will shape the landscape of the global economy over the medium term, as businesses and households seek to repair the damage. The analysis also outlines the difficult policy challenges presented by the overwhelming imperative to take all steps necessary to restore financial stability and revive the global economy, and the longer-run need for national actions to be mutually supporting. The first of two analytical chapters, "What Kind of Economic Recovery?" explores the shape of the eventual recovery. The second, "The Transmission of Financial Stress from Advanced to Emerging and Developing Economies," focuses on the role of external financial linkages and financial stress in transmitting economic shocks.