全球经济还不容乐观

飞雪寒冰

The landscape of Jackson Hole, Wyoming, where central bankers gathered at their annual conference last week, is spectacular and forbidding. Jagged peaks and vast empty spaces stretch across the horizon. For the attendees, however, it was both a vista and a metaphor. Having lived through a precipitous global economic drop, they now must forecast how steep or flat will be the incline of recovery.
怀俄明州Jackson Hole的景色壮观而令人生畏。各国央行人士日前聚集在这里召开年会。映入人们眼帘的是层峦叠嶂的群山和辽阔的空间。然而，对于与会者而言，这片景致寓意深刻。他们已走过此次全球经济低迷的陡峭路段，如今他们必须作出判断：复苏之路有多陡峭？或者说有多平坦？

Ben Bernanke, chairman of the Federal Reserve, painted a sober but reassuring picture of US prospects. The basis for sustained recovery is in place, and canny Fed officials are now alive to the dangers of both deflation and inflation. Similarly Jean Claude Trichet, head of the European Central Bank, spoke about how the dust had begun to settle on the crisis. Policymakers and financial markets seem to be looking at what comes next.
美联储(Fed)主席本•伯南克(Ben Bernanke)为美国前景描绘了一幅平乏但令人安心的画面。持续复苏的基础仍在，谨慎的美联储官员现在意识到了通缩和通胀两种风险并存。同样，欧洲央行(ECB)行长让-克洛德•特里谢(Jean-Claude Trichet)阐述了此次危机已开始要尘埃落定。政策制定者和金融市场似乎正在静观接下来的形势。

飞雪寒冰

Such optimism, however, may be premature. We have analysed data on numerous severe economic dislocations over the past three-quarters of a century; a record of misfortune including 15 severe post-second world war crises, the Great Depression and the 1973-74 oil shock. The result is a bracing warning that the future is likely to bring only hard choices.
然而，这种乐观态度却可能出现得过早。我们对过去75年多次严重经济危机的数据进行了分析；包括二战后15次严重危机、大萧条(Great Depression)和1973年至1974年的石油危机。结果得出了一个令人紧张的警示：未来摆在我们面前的可能只会是艰难的选择。

Our research found real per capita gross domestic product growth tends to be much lower during the decade following crises. Unemployment rates are higher, with the most extreme increases in the most advanced economies that experienced a crisis. In 10 of the 15 episodes we studied, unemployment never fell back to its pre-crisis level, not in the following decade nor right up to the end of 2009.
我们的研究发现，在危机之后的10年里，实际人均国内生产总值(GDP)增速往往会大幅下滑。失业率升高，经历过危机的最发达经济体失业率上升情况最严重。在我们研究的15次危机中，有10次失业率再也没有回落到危机前的水平，此后的10年，以及直到2009年底之前都是如此。

飞雪寒冰

It gets worse. Where house price data are available, 90 per cent of the observations over the decade after a crisis are below their level the year before the crisis. Median prices are 15 to 20 per cent lower too, with cumulative declines as large as 55 per cent. Credit is also a problem. It expands rapidly before crises, but post-crash the ratio of credit to GDP declines by an amount comparable to the pre-crisis surge. However, this deleveraging is often delayed and protracted.
形势还会更糟。在有房地产价格数据可查的情况下，在危机之后的10年里，90%的房地产价格都低于危机前一年的水平。房价中值也较危机前下跌15%至20%，累计跌幅高达55%。信贷也是一个问题。危机前，信贷迅速扩张，但危机之后，信贷与GDP比率的下滑幅度正与危机前的飙升幅度相当。然而，这种去杠杆化经常被拖延。

Our review of the historical record, therefore, strongly supports the view that large destabilising economic events produce big changes in long-term indicators, well after the upheaval of the crisis. Up to now we have been traversing the tracks of prior crises. But if we continue as others have before, the need to deleverage will dampen employment and growth for some time to come.
因此，我们对历史资料的回顾有力地支持了以下观点：破坏经济稳定的重大事件会导致长期指标发生巨大变化，这种变化在危机过去很久后都不会消失。到目前为止，我们一直循着以往危机的轨迹走过来。但如果我们继续像前人一样走下去，去杠杆化的需要将在未来一段时间内抑制就业和经济增长。

飞雪寒冰

At Jackson Hole, policymakers debated whether further measures to stimulate demand were needed. History shows today’s problems could certainly materialise as a consequence of the failure to provide sufficient economic stimulus. In particular, a collapse in financial intermediation can reduce the availability of loans. This lack of access to credit, in turn, makes households and business less able to spend, lengthening and deepening the downturn. In such circumstances slow growth often becomes a self-fulfilling prophecy produced by timid authorities, who neither supported spending nor dealt with the capital-adequacy problems at large banks.
在Jackson Hole，决策者们探讨了是否有必要进一步出台刺激需求的举措。历史表明，作为未能提供足够的经济刺激的结果，今日所说的这些问题确实可能会出现。特别的，金融中介的****会导致贷款供应减少。进而，告贷无门将降低家庭和企业的支出能力。这将延长并加剧经济低迷状况。在这种情况下，经济缓慢增长经常会变成胆小政府制造的一个“自我实现的预言”，这类政府既不会支持消费，也不会去解决大型银行的资本充足率问题。

However, it is also possible that economic contraction and a slow recovery can dent aggregate supply, otherwise known as an economy’s ability to produce efficiently. In this scenario, much less discussed in current debates, a sustained stretch of below-trend investment, alongside the depreciation of human capital that comes from high unemployment, hits the level and growth rate of potential output. That is, the unemployment rate stays high because it has been high.
然而，经济萎缩和缓慢复苏的形势也可能会削弱总供给，或称经济的有效生产能力。在这种情况下，（目前的辩论对此讨论较少）投资持续低于趋势水平的局面，再加上高失业率导致的人力贬值，将会影响潜在产出的水平和增长率。换句话说，失业率仍会高位运行，因为一直就处于高位。

飞雪寒冰

A prudent post-crisis policy, therefore, must be alert to threats both to supply and demand, not demand alone. But the bigger worry remains the assumption that dust has begun to settle; that the shock from the crisis is temporary, when it is likely to be deep and persistent. Today, as in the past, over-optimistic fiscal authorities are over-estimating tax revenues. Financial supervisors want to believe that troubled banks are temporarily illiquid, not permanently insolvent. And central bankers like Mr Bernanke may soon attempt to restore employment to unattainably high levels. If they do so, the road to recovery will be long, and the lessons of history will have been ignored once more.
因此，审慎的后危机政策必须兼顾供求两方面的危险，而不能只注意需求层面的危险。但更让人担心的仍然是以下这种观点：尘埃已开始落定；此次危机带来的冲击是暂时的——而实际上其影响可能是深远而长久的。眼下，就像过去一样，过于乐观的财政当局高估了税收收入。金融监管者则倾向于认为，陷入困境的银行只是暂时的流动性不足，而非长期的资不抵债。伯南克等央行官员可能不久就会着手尝试将就业率恢复到根本无法达到的高水平。如果他们这样做，复苏之路将是漫长的，历史的教训将再度被忽视。

Carmen Reinhart is a professor at the University of Maryland and Vincent Reinhart is resident scholar at the American Enterprise Institute. This is based on a paper presented at the Jackson Hole Symposium.
卡门•莱因哈特是马里兰大学(University of Maryland)教授，文森特•莱因哈特是美国企业研究所(American Enterprise Institute)常驻学者。