从许多方面来看，全球经济目前的状况已经超过了1930年代的大萧条。很多世界闻名的经济学家，例如2018年诺贝尔奖获得者保罗·罗默，已经将当前的经济衰退等同于1930年代的大萧条，而不是2008年的衰退。我们要做的是分析一些数字。

 

在美国，股市从今年的峰值下跌了35％到本季度的最低点。[1] 信贷市场已经失灵，垃圾债券的信贷息差比国库券高出的基点从300点升至超过1000点。[2]我们对经济的预期越来越悲观，主流政府和金融机构预测第二季度产出将下降25％至35％。[3][4]在短短2周的时间内，美国申请失业救济金人数超过660万，创下历史新高。[5]在2008年经济衰退的过程中，美国共损失了880万个工作岗位。[6]美国财政部长史蒂夫·姆努钦（Steve Mnuchin）预测，到今年夏天，美国失业率可能会上升到20％[7], 甚至更高。

 

但是，这次经济事件与大萧条之间的主要区别在于，大萧条从1929年开始爆发，对股市和就业市场的影响过了三年才有所体现，这次大约只花了三个星期！

 

大多数专家已经相信，与2008年的大衰退相比，这次经济衰退将更加严重。几乎已经没有人再持有一季度GDP仅仅下降10％，并实现强劲的V型复苏这种温和衰退的想法。随着越来越多的数据出炉，这些观点变得越来越站不住脚。而正如我们已经看到的那样，经济经历了自由落体的过程，几乎所有的经济体都停止了运转——这种情形甚至在大萧条时期都没有看到过。

 

如果当前全球经济下行的范围和程度已经可以大萧条相提并论，甚至比大萧条还要严重，那么真正的问题是这会持续多久。经济是像大萧条之后出现“ L”形的长期停滞，需要十年的时间才能恢复，还是会更快恢复？我认为目前还没有确定的结论，因为我们对以下三件事尚未足够了解：1）新冠疫情的流行是否可以被控制；2）疫情在秋季是否会出现第二轮扩散；3）世界各国的政策力度、覆盖范围和有效性。

 

如果有人告诉你，他们知道这些问题的答案，请不要相信他们。

 

首先，没有人可以肯定各国采取的缓和措施是否有效。极为讽刺的是，前不久特朗普还公开宣布这只是一种普通流感，没有什么可担心的，几周后他就向美国公民宣布，如果”只有”10万至24万人死亡，那就说明他的工作很出色！

 

美国的确诊病例已经超过中国，而且这一数字还在不断攀升。美国的缓和策略或半缓和策略并不一定能够阻止病毒传播。两天前，人们还可以自由前往佛罗里达州的海滩，那里的居民大多数都在65岁以上。对美国来说，最乐观的情况是像日本和韩国那样，缓和措施已经奏效，确诊人数增长趋于平缓。但是日本和韩国这些国家进行了很多次病毒检测，并且隔离措施高度严格。而美国真的达到了这个标准吗？

 

第二，即使在本国，我们也不能排除第二轮传染的发生。它可能在复工时发生，也可能在秋天发生。病毒随时可能发生突变，并且以更大的侵略性袭击人类。西班牙大流感突变了几次，而第二波是最致命的。

 

此外，入境封锁措施能持续多久？只要世界上某些地区还没有控制住病毒/疫情——比如很多发展中国家会很快沦陷——入境封锁就必须存在。但是封锁边境意味着GDP的损失。

 

中国的复苏进程与欧洲和美国等其他经济体相比是相当乐观的。我们不能指望全球供应链会立刻恢复正常，也不能指望美国的失业工人能够立即找到工作。实际上，由于疫情过后很多公司将开始更多地使用数字化技术，很多人将面临永久性失业。我们也不能假设需求端会立刻恢复正常：如果你习惯了每周去餐厅3次，像美国人或欧洲人那样每周看一次电影，那么你会通过每周去6次餐厅并且看两次电影来弥补失去的这部分需求吗？不会。那部分需求会永远消失。

 

正如经济学家约翰·科克伦（John Cochrane）所说，这就像重启核反应堆一样，你无法将其关闭然后立刻重新打开，这需要花时间。重启的过程越拖延，经济损失就越大。

 

第三，我们假设现在是最乐观的情况，各国政府采取的政策都是正确有效的——那么这意味着世界主要经济体的卫生政策、货币和财政政策都必须毫不犹豫地协同工作。

 

你会认为欧美政府承诺的无限量化宽松、无限流动性、“尽其所能”的政策预示着好消息吗？某种意义上讲，这是个好消息，因为如果不采取这些政策，情况将会更糟。或者也可能正好相反——政府已经预料到情况将会非常糟糕，所有这些激进的政策都预示着我们已经做好了面对这些最坏情况的准备。

 

这就是为什么我们会看到世界主要经济体会采取如此迅速而积极的措施。非常规货币政策方案在美国和欧洲实施通常需要3年时间，而这次只用了3周。通常美国政府需要几个月时间才能通过7,000亿美元的救助方案，而这次只用了几天时间就通过了规模2万亿的刺激计划。我们认为这是个好消息，但实际上它预示的结果是非常负面的。这就是货币政策的“信号效应”，是我目前一直正在研究的学术前沿。

 

刺激计划的成功要求对所有的流动性：从企业到家庭，再到金融机构的偿付能力在很长的一段时间内有所限制——直到找到解决方案。但是没有人能确定这会持续多长时间。

 

此外还有滞胀的问题——是否会出现经济滞胀和通货膨胀？我认为西方国家不会出现通货膨胀，但也有观点认为如果中东国家发生战争，除了石油价格可能暴涨外，严重的负供给冲击也可能使我们陷入类似1970年代的滞胀。我仍然认为，西方国家总需求不足的局面将会持续存在，所以通货膨胀的情况可以得到缓解，但通货膨胀对中国而言却是合理存在的风险。

 

随着数据的持续更新，这些观点也会有所调整。在接下来的几周内，我们将会看到西方国家的缓解对策是否有效，世界上其他地区是否会出现二次感染，以及几个月后，会不会有疫苗的出现。我们仍然不知道秋冬季节是否会出现新一轮的传染，也不知道经济何时才能真正恢复正常。我们必须记住：决定时间线的是病毒，而不是经济学家。经济学家本来就决定不了任何事情，现在这种可能性更小。

 

附英文原文：

 

Economic Depression is now the new Reality

 

By many measures, the global economy has already surpassed the Great depression of the 1930’s. Famous economists around the world, such a the recent Nobel Laureate Paul Romer, are already equating the current economic downturn to the Great Depression of the 1930’s, not the recession of 2008. Recent Nobel Laureate Paul Romer is one just example. But all we have do to is to look at the numbers. Equity markets from its peak this year to its lowest point this quarter has fallen by 35% in the U.S.[1] Credit markets already have already seized up, with credit spreads on junk bonds going from 300 to more than 1000 basis points above treasury bills.[2] Projections of the economy are going down by the day, as mainstream government and financial institutions predict a 25% to 35% loss of output in the second quarter.[3][4] And in a matter of 2 weeks, 6.6 million Americans have filed for unemployment benefit.[5] The total number of employment loss over the entire course of the Great Recession of 2008 in the U.S. was 8.8 million jobs.[6] The Projections from the Treasury secretary Steve Mnuchin is that the U.S. unemployment rate can go up to 20% by this summer.[7]

 

However, the main difference between this episode and the Great depression is that it took 3 years from the trigger in 1929 for this to transpire. This time around---it only took three weeks!

 

By now, virtually everyone has abandoned the idea of a mild recession of a 10% drop in GDP first quarter and a strong V-shaped recovery. But as we get more and more data coming in, these views are getting grimmer and grimmer by the day, by the week, and as we have already seen, the economy has experienced a free-drop---virtually a complete halt of all economic activity---something that was not even seen during the Great Depression.

 

If the size and depth of the current global downturn is worse than the Great Depression, the real question is how long this will last. A danger is that trend output will be permanently lower, and that even when the economy normalizes the countries will be on a permanently lower growth path. This is exactly what happened to countries like the U.K. There will be permanent losses of output, and many jobs which have been destroyed will never come back again. The longer is the protracted recession, the lower the long run trend growth will be.

 

Will wel see an ‘L’ shaped long stagnation like the period after the great depression, where it took ten years to recover, or will it recover much sooner? I don’t think anyone can say with certainty at this point given that we have insufficient information about what will happen to 3 things: the pandemic and whether it can be suppressed; 2) whether there will be a second wave of infection in the fall 3) the extent and scope and effectiveness of government policies around the world.

 

If anyone tells you they know these answers, don’t believe them.

 

First, nobody has confidence on whether mitigation strategies work. It is ironic that weeks after President Trump declared this to be a normal flu and that there is nothing to worry about, he announced to the American citizens that if ‘only’ 100k-240k people die he would have done a terrific job!

 

Already, the U.S. has more infected cases than is registered in China, with numbers still climbing by the day. America’s mitigation policies, or, half-mitigation policies---is not sure to be able to stop the spread of the virus. As of two days ago, people were still going freely to the beach in the state of Florida, where most of residents are above the age of 65. For America, the most optimistic scenario is to be like Japan and Korea, where mitigation has worked, and curves have flattened out. But in those countries they had done a lot of testing, as well as high degrees of self-discipline on social distancing and isolation on the part of the people. Are Americans really living up to that standard?

 

Second, we cannot rule out a second wave of infections---even in this country. It can come about when work re-normalizes, but it can also come about in the autumn, perhaps with a mutation, and attack the population with even greater force and aggression. The Spanish flu mutated several time, with the second wave being the most deadly.

 

And, how long can borders remain closed? So long as some part of the world has not contained the virus---and there will be plenty of developing countries that will soon rise up that curve---borders will have to remain. But closed border means a loss of GDP.

 

By looking at China’s recovering and projecting it onto other economies like Europe and the US is highly optimistic. We cannot expect that global supply chains will just go back to normal as before, and we cannot expect that unemployed workers in the U.S. will find jobs immediately. In fact, many of them will have a permanent loss of jobs because companies will start to adopt more digital technologies after this crisis. We also cannot assume that demand will go back to normal right away. If you were used to go to the restaurant 3 times a week and the movie theatre once a week, as an American or European, are you going to make up for lost time by eating out 6 times a week and going to movies twice a week? No. That part of output is permanently lost.

 

As the economist John Cochrane said, this is like restarting a nuclear reactor. You cannot turn it off and switch it on right back again. It will take time. And the more protracted is this process of restarting, the greater the economic loss.

 

Third, the optimistic scenario assumes that all of the right policies are in place—this means health policies, monetary and fiscal policies in the major economies in the world all have to work conjunctionally, and without any hesitation.

 

Do we think that this unlimited quantitative easing, unlimited liquidity, `doing it whatever it takes’ promised by the European and American governments signal good news? In some ways yes, it is good news, because we would be in an even worse situation in their absence. Or---it could mean just the opposite---they are expecting that times are going to get really bad, so all of this aggressive policies is signalling that we are braced for a really bad run.

 

This is actually why we are seeing such a swift and active response from the major players around the world. Whereas the whole package of the unconventional monetary policy took 3 years to implement in US and Europe, this time it took 3 weeks. Whereas it took the U.S. government months to pass a rescue package of 700 billion dollars, it took less a few days to pass a bill 2.5 times that amount. We think that this is good news, but in fact what it is signalling is very, very bad news to come. This is the ‘signalling effect’ of monetary policy that has been at the frontier of academic research, which I’m also currently working on.

 

The success of the policy requires it to keep a lid on all liquidity, solvency problems from businesses to households to financial institutions---for a long time to come---until there is a solution. But how long will this take ? no one knows for sure.

 

There is also the question of stagflation----will there be stagnation and inflation? I’m not of the view that inflation is about to hit the Western economies, but there is also the compelling argument that a heavy negative supply shock in addition to a possible oil price spike if there is war in the middle east may cast us in another run of the 1970’s stagflation experience. I still believe that there is persistent aggregated demand deficiency in the West to level that off, but inflation is not an unreasonable risk for our own country.

 

These views should adapt as new data comes in. In the next few weeks, we will know whether mitigation strategies work, whether there is a new round of infections in some parts of the world, and in a few months’ time we will know whether a vaccine is more likely. We still do not know whether there will be a new wave in the fall and winter, and we do not know when the economy can realistically return to normal. We have to remember: it is the virus that determines the time line, it is not the economists. It never has been, but even less likely now.

 

注释：

 

[1] 2020年2月12日，道琼斯指数创下历史新高29551点，但12天后的2月24日，美国股市迎来历史性下跌通道，截止3月20日历时25天，道琼斯指数已跌至19173点，跌幅35%。

 

[2]https://www.bloomberg.com/news/articles/2020-03-21/u-s-junk-bonds-enter-distress-spreads-top-1-000-basis-points

 

[3]http://finance.eastmoney.com/a/202003301437210439.html

 

[4]https://fortune.com/2020/03/23/morgan-stanley-goldman-sachs-estimate-coronavirus-economic-pain/

 

[5]https://www.bloomberg.com/news/articles/2020-04-02/u-s-jobless-claims-doubled-to-record-6-65-million-last-week

 

[6]https://www.bls.gov/opub/mlr/2011/04/art1full.pdf

 

[7]https://www.cnbc.com/2020/03/18/mnuchin-warns-senators-of-20percent-us-unemployment-without-coronavirus-rescue-source-says.html

 

文章原载于网易研究局（2020年4月6日）