魏尚进：美国一旦收紧货币政策，两类国家会遭遇危机

来源：中国财富管理50人论坛

中国财富管理50人论坛学术成员、哥伦比亚大学终身讲席教授、亚洲开发银行前首席经济学家魏尚进近日在《复旦金融评论》撰文表示，美国的通货膨胀持续加速，5月的消费者价格与去年同期相比上涨5%，对此需要保持警惕不仅仅是美国的中央银行。全球政策制定者尤其是许多金融脆弱的经济体的政府也应做好准备，迎接美国利率上升快于并早于多数预测的风险。在美国突然收紧货币政策之前，高危经济体的自救措施可能是增强汇率弹性、减少外币贷款和增加外汇储备。

以下为文章全文。

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美国的通货膨胀持续加速，5月的消费者价格与去年同期相比上涨5%，对此需要保持警惕不仅仅是美国的中央银行。全球政策制定者尤其是许多金融脆弱的经济体的政府也应做好准备，迎接美国利率上升快于并早于多数预测的风险。

美联储在过去12个月已经多次大幅上调了通胀预期。决定利率政策的联邦公开市场委员会成员在6月中旬的会议上估计，2021年个人消费支出的全年通胀率将达到3.4%。这比3个月前对全年通胀的预测中值高出整整一个百分点，更是一年前对2021年全年通胀水平预测的两倍多。

美国通胀上升背后反映的是临时性和结构性因素的综合作用。例如，与疫情相关的部分城市封锁导致产能下降，但大规模的政府刺激计划维持住了家庭部门的需求，并且使其中许多行业的需求超过了供应。一旦产能重新释放全部潜力，这部分造成价格上涨的因素就可能消失。

尽管不少美联储官员认为当前的通胀上升主要由暂时性因素造成，但当前通胀也具有重要的结构性因素，与疫情并不完全相关。首先，从2008年以来，美国的货币政策一直处于扩张状态。尽管美联储为应对疫情引发的衰退，进一步增加了货币供应；但早在疫情爆发之前，美国的货币政策就非常宽松，即使在美国失业率处于几十年低位时也不例外。

此外，美国前总统特朗普对从中国进口商品大幅加征关税，在三年时间将关税税率均值从2018年前的约3%提高到20%以上。进口商品价格提高，对美国低收入家庭的影响尤为显著。对华加征关税也拉升了从越南和墨西哥等国进口商品的在美国国内的价格，以及许多美国制品的国内价格，因为这些产品是从中国进口商品的替代品。另外，因为特朗普也对从中国进口的许多零部件加征关税，导致下游产品的价格随后上涨。拜登总统迄今为止还未对特朗普关税做出修正。

最后，特朗普2017年的减税政策和他及拜登总统随后的几波财政刺激计划都提振了总需求，进一步增加了总体价格上涨的压力。许多经济学家、包括一些民主党派的经济学家都认为，相对于美国真实的产出缺口，拜登的1.9万亿美元“疫情救援计划”远远超出了恢复经济增长的必要规模。

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美国通胀上升会对国际社会产生什么影响？我们需要关注的一大风险，就是美联储收紧货币政策会有突然的动作：相比于目前美联储自己公布的相对温和的3.4%年通胀率预测，美国利率上升时间点可以更早、幅度可以更猛。目前比较温和的通胀率预测的前提是公众心里维持着一个“物价稳定锚”，也就是大多数美国家庭、企业和投资者依然相信，美联储既聪明又能干，总能够及时并适度地调整货币供应量，以防止通胀失控。

但是，如果美联储总是未能将通胀保持在理想的2%目标附近，那么公众的“通胀锚”就是脆弱的。到这个时候，除非美联储大幅提高利率，否则员工的工资要求和公司的价格制定都可能开始反映通胀飙升至5%或以上的可能性。

历史经验表明，如果美国利率大幅上升，两类国家可能会遭遇严重的金融和经济危机。第一类是外币债务比较严重的国家，它们向外国银行或在国际债券市场借款，本国的投资或消费比较依赖这样的资金。其中一些国家有大量短期外币贷款负债（到期时间不足一年）而外汇储备又相对较低。一旦美国利率上升，这些国家借新债还旧债发生困难，就特别容易发生严重的债务或银行危机。

第二类是采用固定汇率但其货币又被高估的国家。这些国家很容易在美国利率上升时受货币挤兑和汇率危机的影响。因此，如果美联储大幅收紧货币政策，我们可以预计，在未来2到5年内中南美洲、非洲和亚洲将出现一系列债务和货币危机。由于巨额的外币贷款和高估的固定汇率并不相互排斥，一些国家可能会同时遭受几种类型的危机。（因为这里会包含一些从中国获得大量融资的国家，所以这一风险也需要得到中国有关方面的关注。）

这就是为什么美国的通胀和利率政策对这么多的国家都如此重要。美国一打喷嚏，世界上的许多其他国家就感冒。但其他国家不应指望美国因此改变其货币政策行为，也不应指望国际货币基金组织或七国集团能够引导美国的利率走势更具全球视野。

没有列入以上两种风险类别的国家也需要应对输入性通胀的挑战。以中国为例，尽管中国目前外币负债金额较小并同时保持高水平的外汇储备，但中国对输入性通胀也深感担忧。为防止输入性通胀加剧国内通胀，中国人民银行需要根据情况及时收紧对经济的流动性供给。为了使得货币政策调节有效，中国人民银行需要或者引入更大的汇率灵活性，或者收紧资本控制。从长远来看，选择前者对经济有利得多。

在美国突然收紧货币政策之前，可能遭遇风险的经济体需要抓紧时间实施自救措施。这些经济体可能还有六个月左右的窗口期，建议它们增强汇率弹性，减少对外币贷款的依赖，与此同时增加外汇储备。

The Global Dangers of Rising US Inflation

SHANG-JIN WEI

Editor-in-chief of Fudan Financial Review

Professor of Finance and Ecnomics of Columbia University

Former Chief Economist of Asian Development Bank

NEW YORK – As US inflation continues to accelerate， with consumer prices increasing 5% year on year in May， it is not only the US Federal Reserve that needs to remain vigilant． Policymakers around the world – and in vulnerable economies in particular – also should prepare for the possibility that US interest rates will rise faster and sooner than most forecasts currently predict．

After all， the Fed has raised its inflation forecasts significantly multiple times over the last 12 months． At its mid-June meeting， the policy-setting Federal Open Market Committee estimated that whole-year inflation in 2021 for personal consumption expenditures would be 3.4%． That is a full percentage point higher than their median projection in March， and more than twice the level forecast back in June 2020．

The rise in US inflation reflects a combination of temporary and structural factors． For example， while partial pandemic-related lockdowns have caused production to decline， large government stimulus programs have sustained household demand， which exceeds supply in many sectors． This component of today’s price increases would presumably disappear once output returns to its full potential．

But although Fed officials regard the current increase in inflation as largely transitory， it also has notable structural causes that are not entirely linked to the pandemic． For starters， US monetary policy has been on expansionary steroids since 2008． While the Fed’s response to the pandemic-induced recession increased the money supply further， policy was very loose well before the COVID-19 crisis even when US unemployment at a multi-decade low．

In addition， former President Donald Trump’s aggressive tariff increases on imports from China – from an average of about 3% in 2018 to over 20% within three years – raised the prices of imported goods， especially for low-income US households． They also increased the domestic prices of goods imported from countries such as Vietnam and Mexico， as well as those of US-made products that are substitutes for Chinese imports． As some of the higher tariffs are on parts and components imported from China， they also produced subsequent increases in the prices of downstream products． President Biden has yet to correct the Trump tariffs．

Lastly， Trump’s 2017 tax cut and the subsequent fiscal stimulus programs under both Trump and President Joe Biden have boosted aggregate demand， adding to the upward pressure on prices． Many economists， including some prominent Democratic-leaning ones， think Biden’s $1.9 trillion COVID-19 relief package is much larger than necessary given the estimated size of the US output gap．

To anticipate the international consequences of higher US inflation， we need to recognize the risk that the Fed may tighten monetary policy more suddenly and dramatically than its current 3.4% inflation forecast might suggest． An important mechanism underlying the current relatively modest inflation is a psychological price stability anchoring by the public． That is， a majority of US households， firms， and investors still believe that the Fed will be both wise and capable， and will adjust the money-supply spigot in a timely， measured way to prevent inflation from getting out of hand．

But such “inflation anchoring” could prove fragile if Americans see more evidence of the Fed failing to keep inflation near its desired 2% target． Should that happen， both employees’ wage demands and firms’ price-setting will start to reflect the possibility that inflation could shoot up to 5% or more unless the Fed applies the brakes by raising interest rates aggressively．

If US rates rise sharply， history tells us that two types of countries may experience serious financial and economic difficulties． The first group comprises economies that finance a significant part of their investment or consumption with foreign-currency debt， by borrowing either from foreign banks or on international bond markets． Countries with large short-term foreign-currency debts （with less than one year to maturity） and relatively low foreign-exchange reserves are particularly vulnerable to a severe debt or banking crisis．

The second group consists of countries with an overvalued fixed exchange rate， which makes them vulnerable to a run on their currencies and an exchange-rate crisis． So， if the Fed tightens policy significantly， we can expect to see a number of debt and currency crises in Central and South America， Africa， and Asia in the next 2-5 years． Because significant foreign-currency debt and overvalued fixed exchange rates are not mutually exclusive， some countries may suffer several types of crisis． （As they may include a number of countries that have obtained significant financing from China in recent years， this risk also warrants attention from China．）

This is why US inflation and interest-rate policy is so important to so many． When the United States sneezes， the rest of the world may catch a cold． But other countries should not expect America to conduct its monetary policy any differently as a result， and nor should they count on the International Monetary Fund or the G7 to be able to direct US interest-rate movements to be more globally minded．

Even countries not in either of the risk categories will need to address the challenge of imported inflation． China， for example， is deeply concerned about this， even though it currently has relatively modest foreign-currency debts and retains a high level of foreign-exchange reserves． To prevent imported inflation from fueling domestic inflation， the People’s Bank of China would need to tighten its own supply of liquidity to the economy． To be effective， it has to either introduce more exchange-rate flexibility or tighten its capital controls– the former will be a lot better for the economy in the long run．

At-risk economies may have six months or so to implement self-help measures before any sudden US monetary-policy tightening happens． They are well advised to use it to make their exchange rates more flexible， reduce their reliance on foreign-currency debt， and increase their foreign-exchange reserves．

*作者魏尚进现任复旦大学泛海国际金融学院学术访问教授、哥伦比亚大学金融与经济学终身讲席教授、曾任哈佛大学公共政策学副教授，于2014-2016年间任亚洲开发银行首席经济学家，曾获2019年度当代经济学奖、2015年度与2020年度孙冶方经济学论文奖、2014年张培刚发展经济学优秀论文奖、2016年度与2020年度浦山世界经济优秀论文奖。

*本文仅代表作者个人观点，编译：潘琦。

（责任编辑：王蕾）

责任编辑：戚琦琦