THE ECONOMIST: slumpometer

conomics focus

The global slumpometer

Nov 6th 2008
From The Economist print edition

Rich countries face their deepest recession since the 1930s. For poorer nations it could still be relatively mild

MANY economists are now predicting the worst global recession since the 1930s. Such grim warnings discourage spending by households and businesses, depressing output even more. It is unfortunate, therefore, that there is so much confusion about what pundits mean when they talk about a “global recession”.

America, Britain, the euro area and Japan are almost certainly already in recession according to the popular rule of thumb of two successive quarters of falling GDP. But is the R-word really justified for the world as a whole? In an updated World Economic Outlook, published on November 6th, the IMF predicted that world GDP growth would fall to 2.2% in 2009, based on purchasing-power parity (PPP) weights, from 5% in 2007 and 3.7% in 2008. In the past, the IMF has said that global growth of less than 3% implied a world recession, so its latest forecasts would push the world over the edge. Some forecasts by private-sector firms are even gloomier, with several now predicting global GDP growth of no more than 1.5% in 2009.

But why does the IMF think that a world economy growing by less than 3% a year is in recession? To many people, growth of 2.9%, say, sounds pretty robust. Surely a drop in output is required? The trouble is that there is no agreed definition of a global recession. The popular benchmark used in developed economies—two successive quarters of decline—is not helpful when looking at the world as a whole, because many emerging economies do not report seasonally adjusted quarterly GDP figures. Also, downturns are rarely perfectly synchronised across countries, so even if most countries contract at some stage during a two-year period, global GDP growth may not turn negative. Indeed, global GDP has never fallen in any year since the 1930s Depression. Its worst years since then were 1982 and 1991, with growth of 0.9% and 1.5% respectively (see left-hand chart).

World growth also needs to be adjusted for rising world population. The IMF suggests that a sufficient (although not necessary) condition for a global recession is any year in which world GDP per head declines. In each of the downturns in 1975, 1982 and 1991, growth in world GDP per head turned negative. By contrast, in 2001, despite much talk of “the mother of all recessions”, global GDP per head expanded by around 1%. The annual growth rate in world population has now slowed to 1.2%, so recent GDP forecasts would still allow average world income per head to rise.

If market exchange rates are used to measure world output instead of PPPs, then some recent forecasts would imply a fall in world GDP per head. However, the IMF believes that PPP weights are more appropriate, because a dollar buys a lot more in poor countries than in America, thanks to lower prices. Converting China’s GDP into dollars at market exchange rates therefore understates the true size of its faster-growing economy and, in turn, understates world growth.

The IMF’s definition of global recession also takes account of the fact that the trend growth rate in emerging economies is higher than in developed ones, so even a steep downturn will leave GDP still expanding. A growth rate of 4% would count as a boom in America, but a recession in China. Nevertheless, some economists reckon that the IMF’s 3% benchmark for global recession may be too high. UBS, for instance, suggests a demarcation point of 2.5%. Even the IMF now seems less sure. At the original launch of the World Economic Outlook in October, Olivier Blanchard, the fund’s chief economist, said “it is not useful to use the word ‘recession’ when the world is growing at 3%”.

When tracking such diverse economies, it does make much more sense to define a global recession not as an absolute fall in GDP, but as when growth falls significantly below its potential rate. This can cause anomalies, however. Using the IMF’s definition (ie, growth below 3%), the world economy has been in recession for no fewer than 11 out of the past 28 years. This sits oddly with the fact that America, the world’s biggest economy, has been in recession for only 38 months during that time, according to the National Bureau of Economic Research (the country’s official arbiter of recessions), which defines a recession as a decline in economic activity. It is confusing to have different definitions of recession in rich and poor economies.

Growing apart

Before proclaiming global recession, it is also important to consider the extent to which a downturn has spread around the world. As stockmarkets and currencies have slumped in emerging economies and some governments have had to knock on the IMF’s door, it might appear as if these economies are being hit harder than rich countries. Even in China, growth seems to be slowing sharply, prompting the government to lift its quotas on bank lending at the start of this month. Yet most emerging economies are still widely expected to hold up much better than in previous global downturns.

It is only really the developed world that faces severe recession (see right-hand chart). The IMF’s revised November figures now forecast that the advanced economies will shrink by 0.3% in 2009, which would be the first annual contraction since the war. The IMF has become markedly more bearish on emerging economies since October, revising its forecasts downward by an average of a percentage point. But emerging economies are still tipped to grow by around 5%. This is a sharp slowdown from recent growth of 7-8%, but still above their average growth rate over the past three decades and considerably higher than their typical growth in previous global downturns.

These numbers could of course, be revised down still further. But if broadly correct, this could be a relatively mild downturn for emerging economies. Real income per head is still expected to increase next year in countries that account for well over half of the world’s population. Indeed, if the developed world as a whole suffers an absolute decline in 2009, next year is set to be the first year on record when emerging economies account for more than 100% of world growth.