[2008.11.08] 经济聚焦：全球经济”衰退计”

Economics focus
经济聚焦

The global slumpometer
全球经济”衰退计”

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
发达国家面临自1930年代大萧条以来的最大衰退，而发展中国家的情况仍相对温和

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”.

现在许多经济学家预计：自1930年来以来的全球最大经济衰退即将上演。如此残酷的警告重挫了私人消费以及商业贸易的信心，而产出则下降更多。这是非常不幸的，因此，当专家说到”全球经济衰退”时，他们究竟要表达什么意思，我们还有诸多的困惑。

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.

根据流行的经验判断方法（连续两个季度GDP下降），欧美及日本已经陷入衰退了。但是”衰退”这个字眼对整个世界适用吗？在11月6日出版的最新一期《世界经济展望》中，国际货币基金组织（IMF）根据购买力平价测算，预计世界经济GDP增长率会从2007年的5％和2008年的3.7％降至2009年的2.2％。过去，IMF曾表示如果世界经济低于3％则意味着世界经济衰退，因此它最近的预测已经把世界经济推到衰退的悬崖之外了。一些私人公司的预测则更为严峻，现在已经有好几家公司预计2009年世界经济增长率不会高于1.5％。

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).

但是为何IMF认为世界经济增速低于3％就是衰退呢？对于许多人来说，增速达2.9％意味着经济相当强健呀。的确要一个经济产出的下降才算数吗？问题是现在对于世界经济衰退没有一个一致同意的定义。发达国家同行的标准（连续两个季度经济下降）对于整个世界来说并不适用，因为许多新兴市场国家并不公布调整过的季度GDP数字。同样的，大多数国家的经济下降时间并不一致，所以即使许多国家在一个两年的周期内都有一段时间经济下降，但是整个世界经济不一定出现负增长。事实也确实如此，世界GDP自1930年代大萧条以来就从来没有出现过负增长，其最差的年份是1982年和1991年，但是那两年的经济增速分别为0.9％和1.5％（如左图所示）。

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.

世界经济增长同样需要根据世界人口增长而做出调整。IMF认为世界年度人均GDP下降是全球经济衰退的一个充分条件（而不是必要条件）。在每次经济下降的年份例如1975年，1982年和1991年，世界人均GDP都出现了负增长。相对而言，在2001年，尽管有许多（那一年是）”所有衰退根源”的说法，但是那年世界人均GDP增长了1％。世界人口年度增长率现在降至1.2％，因此最近的GDP预测仍然会使得世界人均收入上升。

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.

如果用市场汇率取代购买力平价来衡量世界经济产出的话，最近的预测则意味着世界人均GDP的下降。然而，IMF认为购买力平价标准更为合适，因为一美元可以在贫穷国家购买的东西比美国多许多，这也多亏了其价格低廉（译者注：这里也就说其国家货币汇率很低）。如果将中国GDP以市场汇率转换为美元则少算了其更快经济增长的真实规模，也少算了世界经济增长的规模。

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%”.

IMF对世界经济衰退的定义也考虑到了新兴国家趋势增长率比发达国家要高的因素，即使这些新兴国家经济下滑严重，但是其GDP 仍然会增长。4%的增速对美国来说意味着繁荣，但对中国来说则意味着衰退。然而，仍有一些经济学家认为IMF3％的标准太高了。UBS(瑞银集团)认为标准应该定在2.5％。即使IMF，现在对其标准也不太确定了。在《世界经济展望》十月份创刊号上，IMF首席经济学家Olivier Blanchard表示：”当世界经济增速在3％时，使用‘衰退’的字眼并不令人满意”。

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.

在跟踪监测了不同的经济体后，我们发现在定义世界经济衰退时，使用GDP增长率显著低于其可能的增长率比使用GDP下降的绝对值作为标准更为合理。然而，这可能导致异常现象。使用IMF的定义（即是，增速低于3％），世界经济在过去28年中衰退的时间不少于11年。然而这是非常奇怪，因为根据美国国家经济研究局（美国经济衰退的官方裁定者）的定义（经济活力的下降），美国这个世界最大的经济体在过去 28年内的衰退时间仅为38个月。对于发达国家和发展中国家衰退的不同定义确实让人感到困惑。

Growing apart
朝不同方向发展

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.

在宣布世界进入衰退前，必须首先重点考虑经济下降在全球蔓延的程度。随着股票和货币在新兴国家的暴跌以及有些政府已经开始向IMF求援，看来这些新兴经济体可能会比那些发达国家受打击更大。即是在中国，经济增速下降也非常明显，这也促使中国政府在本月初提高其银行贷款配额。然而绝大多数新兴国家仍然预计会比在上次衰退时表现的更好。

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.

发达国家确确实实正在面临极其严重地衰退。IMF十一月份修正的数据预计，发达经济体会在2009年经济衰退0.3％，这是自二战以来首次年度经济出现负增长。而IMF自10月以来对于新兴经济体也开始明显看跌，修正下调其增长率一个百分点。然而新兴经济体仍有5％左右的增长率。虽然这是从最近7％到8％增长率的大幅下跌，但是仍比其过去三十年的平均增长率要高而且也高于其在之前全球经济下降时的典型增长率。

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.

这些数据肯定会继续向下调。但是如果上述数据大体正确的话，对新兴经济体来说这是个相对温和的经济下降。在这些占世界人口超过一半的国家，人均实际收入预计在明年仍会增长。确实如此，如果整个发达国家会在2009年遭受一个绝对的经济衰退，明年应该是创纪录的一年：这是新兴国家第一年占超过世界100％的增长。

译者：rushor  http://www.ecocn.org/bbs/viewthread.php?tid=15273&extra=page%3D1