全球貿易增長停滯 貿易峯值假說站不住腳

Since 2011, global trade growth has been stagnant.

全球貿易增長自2011年以來陷入停滯。

With protectionist sentiment intensifying in the US and Europe, and with China appearing to pivot away from export-oriented growth strategies, a hypothesis informally known as peak trade has become increasingly popular.

隨着美國和歐洲的保護主義情緒升溫，以及中國似乎告別出口導向型的增長策略，一種被非正式稱爲貿易達到峯值的假說日益流行起來。

According to this view, the past five years of stagnant trade growth is not temporary, but instead reflects fundamental changes to the global economy that will drive continued stagnation in global trade over the next decade and beyond.

按照這種假說，過去5年貿易增長停滯並非是暫時的，而是反映出全球經濟基本面的改變，這些改變將推動今後十年甚至更久的全球貿易持續停滯。

This view has important implications for global asset markets in at least two ways.

這種觀點至少在兩個方面對全球資產市場具有重要潛在影響。

First, trade is often seen as an engine of global growth, and the sputtering of this engine over the past five years (and the idea that it has permanently stalled) has been widely interpreted as an important reason to be sceptical of global growth in the long run — a view that is baked into the very low levels of long-dated bond yields in advanced economies.

首先，貿易往往被視爲全球增長引擎，而過去5年這個引擎失去後勁（以及它永久性停擺的觀點）被普遍解讀爲全球長期增長難以爲繼的重要理由——這種觀點導致發達經濟體中的長期債券收益率處於非常低的水平。

Second, peak trade implies long-run pessimism for the assets of economies particularly dependent on trade, including many emerging markets.

其次，貿易達到峯值意味着人們對特別依賴貿易的經濟體（包括許多新興市場）的長期資產前景應該感到悲觀。

Our recent work, however, pushes back against three key variants of the peak trade hypothesis.

然而，我們最近的研究發現，3種關鍵的貿易達到峯值的假說不成立。

First, it has been noted that the measured sensitivity of trade growth to GDP growth — the trade beta — has fallen from above 2 in the early 2000s to near, and even below 1; the value at which global trade growth simply keeps up with global GDP growth.

首先，有人指出，貿易增長對GDP增長的可測量敏感度（貿易貝塔係數）從本世紀初的高於2，降至接近甚至低於1的水平；這一水平表明全球貿易增長僅僅與全球GDP增長持平。

However, a detailed look uncovers little convincing evidence that trade has become less responsive to growth over the past 20 years.

然而，仔細研究就會發現，沒有令人信服的證據表明貿易對增長的敏感度在過去20年出現下降。

For example, shifts in the measured trade beta fit awkwardly with shifts in global trade growth: estimates of the trade beta increased in the late 1990s (as trade stagnated), then fell dramatically in the early 2000s (as trade boomed), suggesting that we should not read too much into these large recent fluctuations in the measured trade beta.

例如，可測量貿易貝塔係數的變動與全球貿易增長的變動令人尷尬地不能同步；上世紀90年代末貿易貝塔係數估計值上升（這時候貿易停滯），隨後在本世紀初大幅下降（這時候貿易繁榮），這似乎表明我們不應過度解讀可測量貿易貝塔係數近期的大幅波動。

Second, the global trade slowdown of 2011 was more severe than predicted by observable short-run shocks, prompting many to conclude that forces operating over very long time horizons, and with the potential to drive trade growth still weaker in coming decades, have driven the slowdown.

第二，2011年的全球貿易放緩程度超過了短期劇烈衝擊所顯示出的水平，這促使許多人斷定，推動這一放緩的是長期因素，有可能在今後幾十年進一步壓低貿易增長。

However, we track the nearly 400,000 separate trade flows over the past 20 years, and find their growth rates have returned to baseline levels that, while low, are close to their longer-run histories.

然而，我們追蹤了過去20年近40萬項不同的貿易流動，結果發現它們的增速回到了基線水平——儘管低，但接近它們的長期歷史水平。

In other words, 2011 was not the beginning (or the middle) of a downward deviation from a 70-year trend of globalisation, but instead marks the end of a decade-long upward deviation from this long-run trend: the trade boom of the 2000s.

換言之，2011年並非是70年全球化趨勢下行偏離的開始（或者中途），而是標誌着這種長期趨勢持續十年的上行偏離（本世紀頭十年的貿易繁榮）的結束。

Third, many observers suggest that, by beginning to turn away from export-led growth models, EMs — and especially China — have driven the trade slowdown and will weigh on trade growth in coming decades.

第三，許多觀察人士表示，新興市場（尤其是中國）開始放棄出口導向型增長模式，這推動了貿易放緩，並將在今後幾十年抑制貿易增長。

However, we find that a slowdown in the demand for tradeables (not an EM-led turn away from exports), especially in Europe (much more than China), played the most prominent role in driving the trade slowdown.

然而，我們發現，可貿易商品需求放緩（而不是新興市場主導的告別出口導向模式）在推動貿易放緩方面發揮的作用最爲顯著，尤其是在歐洲（其影響遠遠超過中國）。

In its most recent World Economic Outlook report, the IMF reached a similar conclusion about the importance of demand in explaining the trade slowdown.

國際貨幣基金組織(IMF)在最近的《世界經濟展望》(World Economic Outlook)報告中得出了類似的結論，即需求對貿易放緩有着重大影響。

In sum, shifts in global demand will continue to shape how trade evolves in the years ahead.

總之，全球需求變化將繼續決定今後多年貿易的演變方式。

Our arguments do not call for a speedy rebound in trade growth, but in our view the distribution of risks to global assets has been too heavily influenced by the idea that positive impulses from trade will never return.

我們並不是說貿易增長將會迅速復甦，而是在我們看來，貿易積極影響永遠不會恢復的說法過度影響了全球資產的風險分佈。

In particular, while extreme pessimism on global trade has bled significantly into long-run pessimism on global growth, our work uncovers little to suggest that this type of outcome should be seen as the most likely scenario.

尤其是，儘管對全球貿易的極度悲觀情緒極大地影響了人們對全球增長前景的悲觀看法，但我們的研究發現，幾乎沒有證據表明應該將這類結果視爲最有可能的情景。

Consequently, we push back against the structural negativity around EM assets that we encounter and are more constructive (as we have been since late 2015).

因此，我們不認可圍繞新興市場資產的結構性負面看法——我們的看法更具建設性，就像我們自2015年末以來的那樣。

Despite their vulnerability to a long-run stagnation in global trade growth, we think such risks are overemphasised and that EM assets — characterised by much improved external balances, high real yields and unchallenging valuations — are well-positioned to benefit when more favourable trade winds return.

儘管新興市場資產容易遭受全球貿易增長持續停滯的影響，但我們認爲此類風險被過分強調了，新興市場資產——其特徵是外部收支平衡狀況大幅改善、實際收益率較高以及估值不高——在更有利的貿易風向迴歸時將處於有利地位。