生產率低迷將導致貨幣政策失效

Throughout the developed world, productivity growth has been remarkably weak.

在整個發達世界，生產率增長都非常疲軟。

Even though we are faced daily with new technological gizmos, growth in output per hour has been dismal.

即便我們天天都能看到科技界的新發明，每小時產出的增長卻令人失望。

Admittedly, some countries have done better than others.

無可否認，部分國家的表現比其他國家好一些。

Between 2007 and 2014 — the latest year for which comparable data are available — output per hour rose over 7 per cent across the US economy while in the UK it was broadly unchanged and in Italy it actually fell 2 per cent.

從2007年到2014年（這是有可比數據的最近年份），美國的每小時產出增長逾7%，而英國大體上沒什麼變化，意大利更是下滑了2%。

Yet even the successes are failures judged by their own history.

然而，以各國自身過往歷史判斷，即便是成功國家也是失敗的。

Other than during the dark days of the early 1980s — when two recessions led to a serious, albeit temporary, loss of output — the US has never before experienced such a fallow period of productivity growth.

除了上世紀80年代初期的黑暗年代——當時先後兩輪衰退均引發了嚴重的、儘管是暫時性的產出下滑——美國從未經歷過生產率增長如此疲軟的時期。

There are many explanations for this, including Lawrence Summers’ revival of secular stagnation, Robert Gordon’s claim that the biggest technological impacts on living standards are in the past and, for what it’s worth,

關於生產率增長疲軟，人們提出了許多種解釋。其中，勞倫斯•薩默斯(Lawrence Summers)重提長期性停滯(secular stagnation)概念，羅伯特•戈登(Robert Gordon)則聲稱，技術對人們生活水平的重大影響已經過去。

my own view that we are returning to economic normality after an extended postwar period of economic catch-up.

而以我個人之見，在經歷了戰後漫長的追補性增長之後，經濟正在迴歸常態。

The Summers view is, in many ways, the most optimistic.

從許多方面來說，薩默斯的觀點最樂觀。

Offer fiscal stimulus — particularly focused on infrastructure projects — in the hope that higher demand will create higher supply.

這種觀點認爲應該提供財政刺激——尤其側重基建項目——希望增加需求會創造更多供給。

Yet the risk is that stimulus will raise government debt with no lasting benefit for the economy.

然而，其中的風險在於，財政刺激會推升政府債務，卻不會爲經濟帶來持續性的好處。

Think of Japan over the past two decades, and US stimulus after the dotcom bubble burst that triggered only a housing boom and bust with no lasting benefit for productivity growth.

這可以參考日本在過去二十年裏的情況，以及美國在互聯網泡沫破裂之後出臺的刺激舉措，後者僅僅引發了房地產的一時性繁榮，卻沒有爲生產率增長帶來持續的好處。

Weak productivity has a corrosive impact on living standards.

生產率低迷會損害人們的生活水平。

Should the post-financial crisis trend continue, in the US by 2021 average incomes would be 16 per cent lower than had the 2 per cent per annum postwar productivity trend been maintained.

一旦金融危機後出現的趨勢持續下去，到2021年，比起戰後生產率年均增長2%的趨勢持續的情況，美國的平均收入水平會低16%。

Tax revenues, healthcare, pensions, wage growth and all the other contributors to a nation’s welfare would be lower.

稅收收入、醫療、養老金、工資增長以及所有其他有益於國家福利的因素都會遭到削弱。

Promises made by politicians across the political spectrum would have to be abandoned.

左中右各路政治家們所許下的承諾都將不得不放棄。

To date, attempts to boost productivity have failed.

到目前爲止，所有提振生產率的嘗試都已失敗。

What was seen as a cyclical economic problem has morphed into a biting supply-side constraint.

所謂的週期性經濟問題已演變成令人痛苦的供應側約束。

Worse, the stimulus aimed at boosting economic growth and limiting unemployment may have inadvertently damaged productivity performance.

更糟糕的是，旨在提振經濟增長和減少失業的刺激性舉措，可能無意間損害了生產率。

Exceptionally low interest rates and quantitative easing may have lifted asset prices indiscriminately, crimping capital markets’ abilities to separate productive wheat from unproductive chaff.

極低利率和量化寬鬆也許已無差別地推升了資產價格，損害了資本市場分辨具有經濟效益的領域與缺乏效益的領域的能力。

Further, persistently low productivity growth may be neutering monetary policy itself.

更進一步的問題是，生產率增速長期低迷，也許正在導致貨幣政策失去效力。

In a world in which both growth and inflation are structurally low, interest rates will be dragged down to incredibly low levels — precisely the conditions we see today.

在增長和通脹都處於結構性低點的世界裏，利率會被拉低至令人難以置信的低水平——這正是我們今天遇到的狀況。

If, however, interest rates are low on a structural basis, there is nowhere for them to go in the event of a deep recession.

然而，如果利率因結構性原因而處於低位，一旦發生深度衰退，利率將降無可降。

In these circumstances, the entire monetary policy framework is up for grabs.

在這種情況下，整個貨幣政策框架有待努力整改。

Shibboleths will have to be dispensed with.

必須放棄各種陳詞濫調。

At zero rates, central banks may have to work increasingly closely with finance ministries, prioritising the need for co-ordinated action over the desire for independence.

在零利率環境下，央行可能要日益密切地與財政部合作，將協同行動的需要置於獨立自主的意願之上。

Inflation targeting may have to be ditched, perhaps replaced by nominal gross domestic product targeting: a slowdown in real growth would then be countered by a commitment to higher inflation, boosting nominal GDP and limiting the risk of ever more indigestible debt.

通脹目標制或許必須放棄，也許要由名義國內生產總值(GDP)目標制代替，如此一來，可以通過努力提高通脹、提升名義GDP並抑制越來越難承受的債務水平所帶來的風險，來應對實際經濟增速的放緩。

Yet nominal GDP targeting will work only if central banks can credibly demonstrate not just their desire for higher inflation but also their ability to deliver it.

不過，除非央行能夠令人信服地展示其不僅具備提高通脹的意願，也具有達成這一目標的能力，名義GDP目標制纔會奏效。

To date, they’ve not been particularly successful.

到目前爲止，它們在這方面不是特別成功。

And if productivity growth really is permanently lower, expectations of a life of ever-rising prosperity will have to be abandoned.

如果生產率增速真的長期處在低水平，人們將不得不放棄生活會越來越富足的期望。

If the economics are already difficult, the politics will eventually be considerably harder.

如果經濟已是困難重重，政治最終也會寸步難行。