What lies behind the economic data
We are now in one of those phases where highly favourable economic data clash with an anxious mood among large parts of the business community. Contrast for instance the upbeat remarks of the governor of the Bank of England on "a synchronised world recovery" with the warning by Bill Gross of Pimco that the global outlook is at its most uncertain for 20 or 30 years.
A thoughtful explanation of the discrepancy comes from Kenneth Rogoff, formerly chief economist of the International Monetary Fund, in the May issue of the Central Banker. Mr Rogoff was always more outspoken than the typical international official - he gave up a career as a chess grand master to concentrate on economics.
He now puts his finger on a weakness of official assurances by saying "people tend to resist thinking about low probability extreme events". He uses this expression in relation to the risks to consensus economic forecasts of modest US consumer price inflation of some 2 per cent a year stretching ahead. But many low probability events cumulate to a substantial risk.
There are other kinds of extreme events outside the range of conventional forecasts. There are those that may not happen quickly, such as a violent regime change in Saudi Arabia, but which would be very disruptive if they did. There are also dangers that are highly likely, but the timing of which is uncertain.
Mr Rogoff cites the US current account deficit of 5 per cent of gross domestic product, which he, like many others, regards as unsustainable. Suppose, however, this suddenly reverts to balance. For instance, a steep collapse in US house prices could lead to a sharp rise in private savings. Indeed, he believes there is a high risk of a housing slump in the US even though the boom there has not gone as far there as it has in the UK or Australia. But a future correction would need to be accompanied, according to the former IMF economic director, by a drop in the dollar of over 40 per cent in the short run and in the long run of about 12-14 per cent. But he shares the view that fixed exchange rates would worsen matters.
He considers that the US economy has sufficient flexibility to survive the turmoil he foresees. But how would the inflexible economies of Europe and Japan handle a sudden drop in the dollar? "Very poorly I would venture."
There are weaknesses in the world economy that have a high rather than a low probability of doing damage but to an uncertain extent and over uncertain time horizons. Mr Rogoff cites the low value of official short-term rates, the "unusually lax stance of fiscal policy" and global imbalances.
He believes that we underrate the long-term threat to price stability posed by the steady deterioration in budget positions forecast over the Organisation for Economic Co-operation and Development area in the next 30 years, due mainly to ageing populations. Central banks will thus need to strengthen their independence so that "irresistible spendthrift governments" meet "immovable anti-inflation monetary authorities".
Yet he is critical of the obsession with inflation targets over fairly short horizons. He would like central banks to have a longer focus and also take into account output, the exchange rate and asset prices, especially housing, as well as consumer prices.
Meanwhile, what is the immediate world conjuncture? Outside the core euro area there is indeed a pretty vigorous world economic expansion. At the same time inflation rates, although still low, are rising faster than expected. Nor is it only oil. Other commodity prices are creeping upwards and so are core consumer inflation rates. The pattern is that of an economic upturn beginning to press on primary producing capacity, and in the UK on the labour market too.
The last thing required now are policies designed to stimulate activity further. Yet monetary policies are still highly expansionary. Short-term real interest rates in the Group of Seven countries are still negative. In the US, they are minus 1 per cent. In core euro countries, they are around zero. This compares with a normal historical level of, say, 2 or 3 per cent. There is also a gap of over 2?percentage points between prevailing international nominal short term rates and the rates on 10-year government bonds (an upwardly sloping yield curve). Monetary policy is, in the awful US financial jargon, "behind the curve".
It is difficult to escape the conclusion that central banks still practise "the pretence of knowledge". They believe they can estimate phenomena such as the output gap or the rate of inflation to be expected for any specified behaviour of real activity. The sooner they forget these pretensions and move back towards a neutral policy, the better they will be prepared to meet future threats from any direction.
经济数据一片光明的背后
当前，我们处于这样一个时期：经济数据一片光明，可商界有不少人忧心忡忡。比如，英格兰银行行长发表“全球同步复苏”的乐观言论，而美国太平洋投资管理公司(Pimco)的比尔?格罗斯(Bill Gross)则警告说，目前全球经济前景是20至30年来最不确定的。两者形成对照。
在5月号的《央行行长》(Central Banker)刊物中，原国际货币基金组织(IMF)首席经济学家肯尼斯＃罗戈夫(Kenneth Rogoff)对这种矛盾进行了有见地的解读。罗戈夫先生向来比典型的国际组织官员更为直率。早年他为了专注研究经济学而放弃了象棋大师的职业生涯。
如今，他一语道出官方乐观言论的一个弱点。他说：“人们往往不愿考虑低概率极端事件”。他是在评述主流经济预测带有的风险时使用上述措辞的，这些经济预测认为美国消费价格年度涨幅将一直保持在2%左右的适度水平。其实，许多低概率事件积少成多，足以构成重大风险。
还有一些极端事件根本不在常规预测的范围之内。有些事件，如沙特阿拉伯发生暴力政权更替，可能不会很快成为现实，但一旦发生将具有很大的破坏力。另有一些危险情况其实很有可能发生，只是不能确定具体的发生时间。
罗戈夫先生提到，美国的经常项目赤字数额之巨，已占国内生产总值的5%。与其他许多人一样，他认为这是不可持续的状况。不过，人们也不妨推测赤字忽然消失的情形。例如，美国房产市场的突然崩溃，就有望带来私人储蓄的猛增。事实上，罗戈夫先生相信美国房产市场存在相当高的崩溃风险。这位原IMF经济顾问兼研究部主任表示，美国购房热的程度固然还不及英国或澳大利亚，但未来发生的调整将意味着美元比值在短期暴跌40%以上，长期跌落大约12%-14%。不过他也同意，固定汇率将使情况更糟。
他认为，美国经济具备充分的灵活性，能够经受他所预见的动荡。但欧洲和日本经济不具备此种灵活性，它们又将何以应对美元的突然贬值呢？“依我看，它们的表现将很糟糕。”
当前世界经济中某些弱点造成损害的概率非但不低，而且还相当高，只是损害的程度及延续时间难以确定。作为例证，罗戈夫先生援引了低值的官方短期利率，“宽松得异乎寻常的财政政策”以及各种全球性失衡状况。
他表示，根据有关预测，“经合组织”(OECD)国家未来30年内预算状况将逐年恶化(主要是由于人口老化)，而对这种情况对物价稳定构成的长期威胁，我们估计不足。因此，各国央行应加强其独立性，使“不可抗拒的挥霍的政府”遇上“不可动摇的抑制通涨的货币主管当局”。
不过，他对过于关注短期通涨指标的做法提出了批评。他希望各国央行把目光放得更远，并考虑其他因素，如产出、汇率和资产价格，尤其是房产价格，以及消费价格。
那么，世界经济目前正处于什么状态呢？除欧元区主要经济体之外，当前的确出现了颇为强劲的全球性经济增长。与此同时，通涨率虽然仍处于低水平，但其上升速度却快于预期。而这不只是因为石油的关系，其他初级产品的价格乃至核心消费价格也在悄悄上涨。当前的总体局势是，新一轮经济复苏正对初级产品的产能形成压力，在英国还对劳动力市场形成压力。
当前最不需要的，就是那些旨在进一步刺激经济活动的政策。但当下的货币政策依然是高度扩张性的。七国集团国家的短期实际利率仍为负数：美国为-1%，欧元区主要国家大约为零。这些都与2%-3%的正常历史水平形成对照。此外，通行的国际短期名义利率与10年期国债收益率(上升型收益率曲线)间还有2?#20010;百分点的落差。用一句夸张的美国金融行话来说，当前的货币政策“落后于曲线”。
据此，人们很难回避这样一个结论：各国央行仍在不懂装懂。它们自以为对各种局面胸有成竹，包括任何特定真实活动情形下可以预期的产出缺口或通涨率。其实，它们越早摒弃这些自以为是的念头，回归中性政策，就越能更好地针对任何方向上的未来威胁做好准备。
