美聯儲不應過早考慮升息

I cannot recall a moment when the gap between what markets expect the US Federal Reserve to do and what the Fed itself has forecast it will do has been as large. Markets predict that the Fed will raise rates only to 1.6 per cent by the end of 2017; the Federal Open Market Committee’s average forecast is 3.5 per cent.

我想不起曾有哪一個時刻，市場預期美聯儲會做的事跟美聯儲自己預計要做的事差異如此巨大。市場預計美聯儲到2017年底會將利率提高到1.6%，而聯邦公開市場委員會(FOMC)的平均預計值爲3.5%。

Such a divergence raises the risk of volatility and poses a communications challenge for the Fed. More important, it raises the question of what should guide future policy.

這種認知差異會帶來市場波動風險，也讓美聯儲在向市場傳遞信息方面遇到挑戰。更重要的是，它引發了應以什麼來指導未來政策的問題。

Especially after Friday’s very strong employment report, there can be no doubt that cyclical conditions are normalising. The unemployment rate now is at its postwar average level, and continues to fall. Job openings are above their historic average. Other indicators such as the insured unemployment rate suggest a normal or rapidly normalising economy. All of this taken in isolation would suggest that interest rates should not remain at zero much longer.

特別是最近強勁的就業報告出爐之後，週期性狀況正在恢復正常這一點已不再有疑問。眼下失業率處於戰後平均水平，並在繼續下降。職位空缺數量超過歷史平均值。參保失業率(IUR)等其他指標顯示，經濟已迴歸正軌、或正迅速回歸正軌。只從這些來看，說明零利率不應維持太長時間了。

On the other hand, the available inflation data suggests little cause for concern. The core consumer price index has averaged 1.1 per cent over the past six months; if housing costs were stripped out it would be zero. Wages actually fell in December and over the past year employment costs have risen 2.25 per cent which, in conjunction with productivity growth of only 1 per cent, suggests inflation of below 2 per cent. Perhaps most troubling: market indications suggest inflation is more likely to fall than rise .

另一方面，現有通脹數據表明沒有什麼可擔心的。核心消費價格指數(CPI)過去6個月的均值爲1.1%，如果剔除住房成本，則核心CPI爲0。去年12月工資實際上下跌了；過去一年的僱傭成本上漲了2.25%，而生產率僅增長了1%，這意味着通脹率不到2%。最令人不安的或許是：各項市場指標顯示通脹率降低的可能性大於升高的可能性。

The Fed has rightly made clear that its decisions will be data dependent. The further key point is that it should allow the flow of information on inflation rather than on real economic activity to determine its timing in adjusting interest rates. And it should not raise rates until there is clear evidence that inflation, and inflation expectations, are in danger of exceeding its 2 per cent target. Here are four important reasons why.

美聯儲明確表示有關調息的決定將取決於數據，這是對的。更關鍵的一點是，它應根據有關通脹、而不是實體經濟活動的數據決定何時調息，並且不應在有明確證據顯示通脹、以及通脹預期有可能超過2%目標值之前升息。這麼說有四個重要理由：

First, real wages for most workers have been stagnant. Median family incomes are down by 4.5 per cent over the past five years and the economy is about $1.5tn — or $20,000 for the average family of four — below pre-recession estimates of its 2015 potential.

首先，大多數勞動者的實際工資一直停滯不前。過去5年家庭收入中值下降了4.5%，目前的經濟規模比衰退前預測的2015年潛在經濟規模低出約1.5萬億美元，相當於每個家庭（按平均每家4口人計算）低於預測值2萬美元。

In such circumstances efforts to reduce demand and growth require a compelling justification. Yet the idea that below normal unemployment will necessarily lead to accelerating inflation as suggested by the so called Phillips curve is very uncertain. Contrary to such predictions, inflation did not decelerate by much even a few years ago when unemployment was in the range of 10 per cent. Nor was there much evidence of accelerating inflation in the 1990s when the unemployment rate fell below 4 per cent.

在這種情況下，若要採取降低需求和抑制增長的措施，需有充分理由。然而，所謂的菲利普斯曲線(Phillips curve)所描繪的情形——低於通常水平的失業率肯定會導致通脹加速上升——存在極大不確定性。與菲利普斯曲線預測的情形相反，就在幾年前，當失業率達到10%水平的時候，通脹也並沒有降多少，而上世紀90年代，失業率降至4%以下時，也沒有多少證據顯示通脹升高。

Second, if inflation were to accelerate a bit this would be a good thing. It is now running and is expected to run below the Fed target. Prices are about 4 per cent below where they would have been if 2 per cent inflation had been maintained since 2007. So there is a case for some inflation above 2 per cent to catch up to the Fed’s price level target path. They may also be a case for inflation a little bit above 2 per cent for the next few years to allow real interest rates low enough to promote recovery when the next recession comes.

其次，假如通脹真的略有升高，那是件好事。眼下通脹率低於美聯儲目標值，並且預計未來將繼續低於目標值。假如通脹自2007年至今一直維持2%，那麼物價水平將比現在高4%左右。因此，讓通脹升至略高於2%是有理由的，這樣可以讓物價水平追趕美聯儲的目標物價水平。考慮到目前的物價水平低於目標水平，讓通脹在未來幾年維持在略高於2%還能夠讓實際利率變得足夠低，以便在下一次衰退到來時爲推動復甦提供空間。

Third, a plane that accelerates too rapidly as it takes off may cause passengers discomfort while a plane that accelerates too slowly may crash at the end of the runway. Historical experience is that inflation accelerates only slowly so the costs of an overshoot on inflation are small and reversible with standard tightening policies. In contrast, aborting recovery and risking a further slowing of inflation is potentially catastrophic — as Japan’s experience demonstrates. So in a world where economic forecasts are highly uncertain, prudence in avoiding the largest risks counsels in favour of Fed restraint in raising rates.

第三，飛機起飛時加速太快會讓乘客感到不適，但起飛太慢，飛機可能會墜毀在跑道上。歷史經驗顯示，通脹升高速度並不快，因此通脹超標的成本很小，並且可通過實施常規緊縮政策來補救。相反，讓復甦中斷、冒讓通脹進一步放緩的風險卻可能造成災難性後果——如日本的經驗所示。因此，在這個經濟預測高度不確定的世界裏，出於避免最大風險的審慎考慮，美聯儲應謹慎對待升息。

Fourth, the US has never been more intertwined with the global economy. Higher interest rates and the stronger dollar they would bring would mean greater debt burdens for debtor countries, a growing US trade deficit that damages manufacturing, and growing protectionist pressures.

第四，美國與全球經濟的聯繫從未像現在這樣緊密。更高的利率、以及高息帶來的更強勢美元，意味着債務國的債務負擔將變得更重，美國貿易赤字會增加（不利於製造業），貿易保護主義壓力也會增強。

There is already a danger given all the problems in Europe, Japan and emerging markets that safe haven flows will drive the dollar up to the point where the US economy could be significantly slowed. Raising rates without evidence of rising inflation could dramatically increase real rates and exacerbate these risks.

鑑於歐洲、日本和新興市場的種種問題，目前已經存在這樣的風險：因資金流入避險貨幣，導致美元幣值升高到可能使美國經濟顯著放緩的地步。在沒有證據顯示通脹升高的情況下升息，可能使實際利率大幅上升，加劇上述風險。

None of this is to say that rates should never be raised or that inflation indicators might not justify a rate increase before long. It is to say that the Fed could inject much needed confidence in the economy today and minimise future risks by announcing and following a strategy of not raising rates until it sees the whites of inflation’s eyes.

這些並不意味着我們應無限期推遲升息，也不意味着通脹指標不可能在短期內變得支持升息，而只是說，通過宣佈和遵循這樣一種策略——“在沒有看到通脹的確鑿證據之前不升息”，美聯儲可使人們對經濟重拾信心（這是當前非常需要的），並最大程度地減小未來的風險。

The writer is Charles W Eliot university professor at Harvard and a former US Treasury secretary

本文作者爲哈佛大學(Harvard)查爾斯•W•艾略特大學教授(Charles W Eliot University Professor)，曾任美國財政部長