EMDEs is also estimated to have slowed, from 5.9 percent a year in the mid-2000s to 4.8 percent a year in 2013-17, reflecting the effects of weak investment, adverse demographic trends, and slower productivity growth.

In light of the protracted weakness of economic growth, together with chronically low inflation (persistently below target in most cases), despite unprecedented monetary policy accommodation maintained over several years and historically low long-term interest rates, some observers have argued that advanced economies have been facing “secular stagnation”, owing to structural weakness in aggregate demand (Teulings and Baldwin 2014; Summers 2015; Rachel and Summers 2019).<sup>30</sup> Many factors may have contributed to such demand weakness, including increased saving originating partly from demographic factors and reduced investment spending stemming partly from the reduced costs of capital goods, which have increasingly embodied information technology. Financial crises may also have contributed through higher risk aversion, increased costs of financial intermediation, and increased debt overhangs. Recent research concludes that, in light of the Japanese experience after its banking crisis in the early 1990s, some major euro area economies might suffer a long period of stagnation because of structural headwinds associated with demographic trends and persistent weakness in productivity growth (Hoshi and Kashyap 2015).

# 5. Conclusion

The year 2019 was the tenth anniversary of the last global recession. Yet 2019 also marked an intensifying speculation about whether another such episode was looming. During 2019, global growth forecasts were repeatedly downgraded as a broad-based slowdown enveloped both advanced economies and EMDEs. Trade tensions between major economies led to unprecedented policy uncertainty and took a heavy toll on global industrial production and trade.

In light of the resurgence of interest on the topic, this paper analyzes the main features of global recessions and the ensuing global recoveries and expansions.

What happens during global recessions and recoveries? Both statistical and judgmental methods identify four global recessions since 1950: in 1975, 1982, 1991, and 2009. During these four years, there was a contraction in annual real per capita global GDP and broadbased weakness in the main indicators of global activity. Quarterly data yield similar recession dates and confirm that the duration of a typical global recession is about one year—which is also the average duration of national recessions. Global recessions are highly synchronized events, with severe economic and financial disruptions occurring simultaneously in many countries around the world. Although the four global recessions

> 30 Hansen (1939) argues that the Great Depression could lead to a prolonged period of stagnation and high unemployment because of the decline in the birth rate and excessive savings that constrain aggregate demand. For a theoretical formulation of secular stagnation, see Eggertsson, Mehrotra, and Robbins (2019). Hamilton et al. (2016) argue that the secular stagnation hypothesis confuses a delayed recovery with chronically weak aggregate demand. By examining global real interest rates over eight centuries, Schmelzing (2020) concludes that the current decline in sovereign real rates is a path to converge to the historical trend, rather than a sign of secular stagnation. Others consider the case for secular stagnation to be weak (Rogoff 2013; Taylor 2014).

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