FT社評：美國債券牛市必將終結嗎？

Markets are complex. They aggregate millions of individual decisions, each responding to an economic environment that is wickedly complicated. People, by contrast, seek simplicity. We search for patterns, and insist that life is made up of stories with beginnings, middles and ends. We often see patterns that are not even there.

市場是復雜的。它們匯集了無數(shù)的個人決策，每個決策都是對極端復雜的經(jīng)濟環(huán)境做出的回應。相比之下，人們喜歡追求簡單化。我們在尋找模式，并堅信生活是由開頭、劇中和結局的敘事構成的。我們經(jīng)常找出一些甚至根本不存在的模式。

At the moment, there is an extremely simple, compelling and popular narrative about the US bond market. It goes something like this:

當下出現(xiàn)了一種針對美國債券市場極為簡單、有說服力且頗為流行的敘事。敘述如下：

In 2017 we had a year of synchronised global economic growth, and the US followed the global pattern. This year, the US economy will be further stimulated by a large, deficit-funded tax cut. Unemployment is already low. Before much longer, therefore, wage growth will awaken from its long slumber. Inflation expectations and, in turn, actual inflation will follow. This will keep the Federal Reserve wedded to its plan of raising rates three times this year. At the same time, the Fed will continue to reduce its bond holdings, unwinding the quantitative easing programme. Resurgent inflation, higher short rates and less government purchasing of long bonds will end the longest-standing cyclical trend in finance: the 37-year bull market in bonds.

2017年，全球經(jīng)濟實現(xiàn)了同步增長，而美國緊跟這一全球模式。今年，美國經(jīng)濟將進一步受到大規(guī)模、赤字襄助的減稅政策的刺激。失業(yè)率早已處于低位。因此，用不了多長時間，工資增長將從長期沉睡中復蘇。通脹預期以及實際通脹將隨之復蘇。這將促使美聯(lián)儲(Fed)堅持今年三次加息的計劃。與此同時，美聯(lián)儲將繼續(xù)降低其債券持有量，解除量化寬松計劃。通脹再度抬頭、短期利率上升和政府減少購買長期債券，將終結金融領域中持續(xù)時間最長的周期性趨勢：延續(xù)37年的債券牛市。

There are good reasons to believe this story. The simplest is that yields are, in fact, rising: the 10-year Treasury, at just under 2.6 per cent, is up 50 basis points since September and more than 100 basis points since the mid-2016 bottom. The jittery expectation of higher yields (which is to say, lower bond prices) was evident on Wednesday, when yields bounced, apparently in response to speculation that China planned to limit its purchases of US debt (the speculation turned out to have little grounding in fact).

有充足的理由相信這一敘事。最簡單的一點是，收益率實際在上升：僅略低于2.6%的10年期美國國債收益率，自去年9月以來上漲了50個基點，自2016年中期以來累計上漲逾100個基點。周三，當債券收益率出現(xiàn)反彈時——顯然是對中國計劃限制購買美國國債的猜測的回應(事實證明這一猜測沒有什么依據(jù))——對收益率上升(即債券價格下跌)的緊張不安預期已經(jīng)很明顯了。

Companies are brimming with optimism, according to surveys. When the tax cut was passed various companies, including AT&T and Walmart, announced plans to pass the largesse on to workers in the form of higher wages or bonuses. Meanwhile, some of the biggest names in bond management are publicly stating the good times are over.

種種調查顯示，企業(yè)界充滿了樂觀情緒。減稅法案通過后，包括美國電話電報公司(AT&T)、沃爾瑪(Walmart)在內的很多企業(yè)紛紛宣布計劃以增加工資或獎金的形式把省下的錢發(fā)放給員工。與此同時，債券管理領域一些最知名的公司公開表示，好日子已經(jīng)結束。

Any story this tidy and this popular should be doubted on principle. Its ubiquity is evidence that it has taken on a life of its own. Let us, then, rehearse some of the reasons it might fall to pieces in the year ahead. The most obvious point is that wage inflation may stay in its coma. After the way unemployment and inflation have come apart in recent years, to continue to insist that we have a firm understanding of their relationship would be arrogance. There may, for example, be more slack left in the economy than it appears, keeping inflation tame even if demand gets a kick.

原則上，任何如此完美、流行的敘事都應受到質疑。它的無處不在證明了其自身已經(jīng)具有生命力。那么，讓我們預判一下這一敘事在未來一年可能破滅的一些原因吧。最明顯的一點是，工資增長或將繼續(xù)處于停滯狀態(tài)。自近幾年失業(yè)率和通脹失去關聯(lián)之后，繼續(xù)堅稱我們完全理解它們之間的關系，將是一種傲慢。例如，經(jīng)濟可能會出現(xiàn)實際比看上去蕭條的局面，在這種情況下，即使刺激需求，通脹仍會保持溫和水平。

Next, it may be that even as QE unwinds, ageing demographics and the attendant glut of savings will keep long rates very low. It is worth noting in this context that in real terms, the US is an outlier. Its interest rates are higher than almost everywhere else in the developed world.

其次，有可能即便退出量化寬松政策，人口老齡化和隨之而來的儲蓄過剩仍將使長期利率維持在非常低的水平。在這一背景下值得注意的是，實際上美國是一個例外。美國的利率比幾乎所有發(fā)達國家都高。

Finally, US growth may simply disappoint — either because policymakers tighten rates too quickly or for some other reason. There was lively debate about the size of the stimulative effect the tax cut would have on the real economy. That debate has not been resolved simply because the growth prospects look good now, before the cuts have even come through.

最后，美國經(jīng)濟增長可能只會令人失望——或是因為政策制定者過快收緊利率，或者是出于其他原因。關于減稅對實體經(jīng)濟刺激效應的規(guī)模，也存在著激烈的爭論。這一爭論不會僅僅是因為現(xiàn)在經(jīng)濟增長前景看起來不錯(甚至在減稅成功實施前)就自動化解。

Economic narratives have real economic effects. Widespread belief that inflation is inevitable makes inflation more likely. Still, the history of economic forecasting encourages modesty and, in the bond market, a simple story is never the whole story.

經(jīng)濟敘事會造成真實的經(jīng)濟效應。普遍相信通脹不可避免會導致通脹更有可能發(fā)生。盡管如此，經(jīng)濟預測的歷史鼓勵穩(wěn)重適度，而在債券市場，一個簡單的敘事永遠不可能是全部敘事。