魏尚进：新型冠状病毒会拖累中国经济增长吗?
The following article comes from 复旦金融评论 Author 魏尚进
一些人担心新型冠状病毒爆发使中国经济雪上加霜，会严重拖累2020年的中国与全球的增长率。
我的基本预测是，新型冠状病毒疫情在近期内会继续恶化，感染和死亡病例数量可能在2月的第二或第三周达到顶峰。但我预计疫情将于4月初得到基本控制。
我的估算是，这一病毒对经济的影响虽负但有限。它对中国2020年GDP增长率的影响可能很小，大约降低0.1个百分点。对2020年第一季度的增长影响较大，也许会使当季的年化增长率降低1个百分点，但这将被今年余下时间里高于趋势的增长率大幅抵消。对全球GDP增长的影响将更小。
当然，如果新型冠状病毒危机的持续时间远远超过这一基准假设，它对中国和其他经济体的影响可能会更加严重。即便在这种情况下，重要的是要记住，中国的决策者仍有货币和财政扩张的空间。
新型冠状病毒的爆发在中国和世界其他地区引发警觉是可以理解的。但从经济视角来看，现在恐慌还为时过早。
——魏尚进 中国金融四十人论坛（CF40）学术顾问、复旦大学泛海国际金融学院学术访问教授、哥伦比亚大学终身讲席教授
”新型冠状病毒会拖累中国经济增长吗?
这些担忧合理吗？
魏尚进 资料图
我的基本预测是，新型冠状病毒疫情在近期内会继续恶化，感染和死亡病例数量可能在2月的第二或第三周达到顶峰。但我预计疫情将于4月初得到基本控制。
在此基准情况下，我的估算是，这一病毒对经济的影响虽负但有限。它对中国2020年GDP增长率的影响可能很小，大约降低0.1个百分点。对2020年第一季度的增长影响较大，也许会使当季的年化增长率降低1个百分点，但这将被今年余下时间里高于趋势的增长率大幅抵消。对全球GDP增长的影响将更小。
这种预测借鉴了2003年SARS危机的经历。那场危机导致了2003年第二季度中国GDP增长大幅下滑，但随后两个季度的高速增长基本上抵消了这一颓势。尽管2003年全年的经济增长率约为10％，但当时许多投行经济学家都高估了那场公共卫生危机对经济的负面影响。如果从2000年至2006年的GDP年实际增长率的时间序列来看，很难从数据中看出SARS的影响。
一些人担心这次疫情爆发时正值为期一周的农历新年节庆伊始和传统的寒假旅行之际，这将加剧其对经济的负面影响，因为这个阶段本该是购物、餐饮与旅游的高峰但却因为疫情而没有发生。但是，这种讲法或许忽略了三个重要因素。
首先，今天与SARS之时有一个很大的不同是中国已经进入了互联网商业时代，消费者越来越多地在网上购物。新型冠状病毒造成的线下销售减少，大部分可能会被（快递恢复后的）在线购物的增加所抵消。而且大部分当前取消的度假很可能会被未来的旅行所取代，因为经济宽裕的家庭已经预留了旅行预算。
许多工厂本就安排在农历新年假期中停产，因此疫情爆发的时机可能使进一步停工的必要性降到最低。同样，许多政府机关和学校都按计划本来就会在春节期间关闭。政府刚刚宣布延长假期，但是许多公司会想尽办法在以后弥补回损失的时间。因此，短期的负面影响很可能主要集中在餐饮、酒店和航空业。
其次，所有报告都表明，武汉冠状病毒的致死率不如SARS（尽管它初期的传播速度可能更快）。通过采取主动积极的措施，将确诊和疑似患者与其他人群隔离开来，这也大大增强了更早遏制疫情的机会，进而增加了本季度损失的经济产出将被今年剩余时间增加的经济活动抵消的可能性。
再者，中国贸易谈判代表于1月15日完成了与美国签署“第一阶段”贸易协议。无论当时是否意识到武汉新型冠状病毒的严重性，协议的签署的节点是比较幸运的。通过大量增加从美国（及其他地区）进口口罩和医疗用品，中国可以同时应对公共卫生危机，并履行其在贸易协议下进口更多商品的承诺。
此次的新型冠状病毒对其他经济体的影响将更加有限。在过去的几年中，许多主要经济体中央银行已经开发出模型来衡量中国经济放缓对其经济的影响。虽然这些模型的建立并非用来评估当前的公共卫生危机，但它们确实将各自经济体与中国之间的贸易和金融联系纳入考量。
根据经验，中国GDP增长放缓对美国和欧洲经济体的负面影响的百分比大约是其自身幅度的五分之一。若当前的新型冠状病毒疫情使中国的经济增长率降低了0.1个百分点，那么美国和欧洲的经济增长可能会下降约0.02个百分点。鉴于澳大利亚与中国在大宗商品贸易和旅游业方面更为紧密的联系，这对澳大利的经济增长的影响可能是两倍，但经济增长率下降0.04个百分点的幅度仍然很小。
这样计算的假定是新型冠状病毒不会广泛传播到这些国家并造成直接的破坏。鉴于中国以外的病例数量较少，目前看来不太可能出现这种情况。
当然，如果新型冠状病毒危机的持续时间远远超过这一基准假设，它对中国和其他经济体的影响可能会更加严重。即便在这种情况下，重要的是要记住，中国的决策者仍有货币和财政扩张的空间：与许多其他经济体相比，中国的银行准备金率相对较高，公共部门债务相对于GDP的比例仍然可控。通过在必要时用好这一政策空间，中国政府可以限制当前疫情危机对经济的最终影响。
新型冠状病毒的爆发在中国和世界其他地区引发警觉是可以理解的。但从经济视角来看，现在恐慌还为时过早。
本文转载自微信公众号“复旦金融评论”，根据作者发表于《报业辛迪加》上的“Will the Coronavirus Cause a Major Growth Slowdown in China?”（2020年1月27日）一文翻译，英文原文如下：
向上滑动阅览英文原文
The panic generated by the new coronavirus, 2019-nCoV, which originated in Wuhan, China’s ninth largest cities and a major domestic transport hub, reminds many of the fear and uncertainty at the peak of the 2003 SARS crisis. China’s stock market, after rising for months, has reversed itself in recent days, and global markets have followed suit, potentially reflecting concerns about the epidemic’s impact on the Chinese economy and global growth. Are these worries justified?
My baseline projection is that the coronavirus outbreak will get worse before it gets better, with infections and deaths possibly peaking in the second or third week of February. But I expect that the epidemic to be under control by early April.
Under this baseline scenario, my best estimate is that the virus will have only a limited negative economic impact. Its effect on Chinese GDP growth rate in 2020 is likely to be small, perhaps a reduction on the order of 1/10 of a one percentage point. The effect in the first quarter of 2020 will be big, perhaps lowering growth by one percentage point on an annualized basis, but this will be substantially offset by above-the-trend growth in the rest of the year. The impact on the world GDP growth will be even smaller.
Such a prediction is parallel to the experience of the 2003 SARS crisis. That crisis produced a big decline in China’s GDP growth in the second quarter of that year, which was then largely offset by higher growth in the subsequent two quarters. While the whole year growth rate in 2003 was about 10%, many investment bank economists at the time over-predicted the negative growth impact of the health crisis. If one looks at the time series of annual real GDP growth rates from 2000-2006, it will be very hard to see a SARS effect in the data.
Some fear that the epidemic’s timing – at the start of the week-long Chinese New Year celebration, and in the middle of traditional school-break travels – will exacerbate the economic fallout by keeping many people away from shops, restaurants, and travel hubs. But three important factors may limit the virus’s impact.
First, in contrast to the SARS outbreak, China is now in the Internet commerce age, with consumers increasingly doing their shopping online. Much of the reduction in offline sales owing to the virus will likely be offset by an increase in online purchases (after the resumption of the delivery service). And most of the vacations canceled today will probably be replaced by future trips, because better-off households have already set aside a holiday travel budget.
Many factories have scheduled production stoppages during the Chinese New Year holidays anyway, so the timing of the epidemic may minimize the need for further shutdowns. Similarly, many government offices and schools had planned holiday closures independently of the virus outbreak. The government has just announced an extension of the holiday period, but many companies will find ways to make up the lost time later in the year. The short-term negative impact is thus likely to be concentrated among restaurants, hotels, and airlines.
Second, all reports indicate that the Wuhan coronavirus is less deadly than SARS (although it may have a faster rate of transmission initially). By implementing aggressive measures to isolate actual and potential patients from the rest of the population, the authorities have also improved their chances in containing the epidemic much sooner. That, in turn, increases the likelihood that the lost economic output this quarter will be offset by increased activity in the remainder of the year.
Third, whether or not China’s trade negotiators realized the severity of the Wuhan virus when they signed the “phase one” trade deal with the United States on January 15, the timing of the agreement has turned out to be fortunate. By greatly increasing its imports of facial masks and medical supplies from the US (and elsewhere), China can simultaneously tackle the health crisis and fulfillits promise under the deal to import more goods.
The virus’s impact on other economies will be even more limited. During the last half-decade, many major central banks have developed models to gauge the economic impact of a slowdown in China on their economies. These models were not built with the current health crisis in mind, but they do take into account trade and financial linkages between China and their respective economies.
As a rule of thumb, the negative impact of a decrease in China’s GDP growth on the US and European economies is about one-fifth as large in percentage terms. For example, if the current coronavirus epidemic lowers China’s growth rate by 0.1 percentage points, then growth in the US and Europe is likely to slow by about 0.02 percentage points. The impact on Australia’s economy may be twice as large, given its stronger commodity-trade and tourism links with China, but a 0.04-percentage-point reduction in growth is still small.
Such calculations assume that the coronavirus does not spread widely to these countries and cause direct havoc. This currently seems unlikely, given the low number of cases outside China.
Of course, the impact on China and other economies could be more severe if the coronavirus crisis were to last much longer than this baseline scenario assumes. In that case, it is important to remember that Chinese policymakers still have room for both monetary and fiscal expansion: the banking-sector reserve ratio is relatively high, and the share of public-sector debt to GDP is still manageable compared to China’s international peers. By using this policy space when necessary, China’s authorities could limit the ultimate impact of the current health crisis.
The coronavirus outbreak is understandably causing alarm in China and elsewhere. From an economic perspective, it is too early to panic.