世界應爲強美元時代做好準備

Preparing non-American markets for a strong greenback is not Janet Yellen’s job

對於美聯儲(Fed)主席珍妮特耶倫(Janet Yellen)來說，令美國以外市場爲美元的強勢做好準備，並不是她的本職工作。

As a symbol of how the US punches above its weight, nothing beats the pre-eminence of its currency. The US may account for just a fifth of global gross domestic product, but dollar assets make up three times as great a proportion of global reserves. Most commodity trading uses the greenback as the medium of account.

要尋找一個美國“勉爲其難”的象徵，沒有什麼能比美元的超重要地位更合適了。美國的國內生產總值(GDP)可能只佔了全球總量的五分之一，美元資產佔全球儲備資產的比例卻是上述比例的三倍。絕大多數大宗商品交易，是把美元作爲記賬媒介的。

This influence is telling. A working paper from the Bank of International Settlements found almost $8tn of dollar credit issued to non US borrowers. More recently the IMF pointed out how past episodes of dollar strength have coincided with a rash of emerging market crises. Now that the greenback is surging again — the dollar index is up 20 per cent since last autumn — the implications are moving into focus.

這種影響顯而易見。國際清算銀行(BIS)的一份工作報告發現，發放給美國以外的借款方的美元信貸接近8萬億美元。在更近一些時候，國際貨幣基金組織(IMF)曾指出，過去美元多輪強勢行情，與新興市場的多次危機，是同步發生的。如今，美元匯率再次猛漲——自去年秋季以來美元指數已上漲20%，它的影響正日漸受到關注。

First, some perspective is in order. Although the dollar index rose from 80 in October to 100 in March, such price action is run-of-the-mill when examined over a longer period. Between 1981 and 1985, the same index soared from 90 to 160, before a co-ordinated international effort pushed it all the way back within three years.

首先，某些觀點認爲這種波動很正常。儘管美元指數從去年10月的80上升到了今年3月的100，但從更長時期來看，這樣的匯率波動並不起眼。在1981年到1985年期間，美元指數曾經從90猛漲至160，之後纔在國際社會一致努力下在三年內被全力壓了回去。

Dissecting the dollar is something of an art; a bet on its strength can reflect confidence in the US, or darkening clouds elsewhere and a rush to safe assets. The same IMF paper has shown that rising US rates are beneficial when they reflect optimism about growth, but not if driven by tighter money. On many occasions dollar strength has coincided with fears about growth; last autumn, for example, a spell of global deflation may have helped propel the dollar on its recent run. Of late, attention has focused more closely upon how well the US is doing.

美元的剖析是一種藝術：押注美元走強可以反映出對美國的信心，或者反映了其他地區的烏雲密佈以及對安全資產的搶購。IMF同一份報告顯示，如果美國加息反映了對增長的樂觀看法、而並非出於收緊貨幣政策的動機，那麼它就是有益的。許多時候，美元走強之時，也是人們對增長產生擔憂之時。比如，去年秋天一輪全球通縮，或曾對美元近期匯率上升起了推波助瀾的作用。最近，美國的經濟表現已經吸引了更多注意力。

Indeed, it is striking how US monetary policy pays little direct attention to the dollar’s globe-trotting role. Peruse Federal Reserve statements, or recent comments by its chair Janet Yellen, and you will struggle to find much reference to the world beyond US borders. Ms Yellen is focused on the data, but the data in question is all domestic: unemployment, inflation and GDP. The global economy only matters insofar as it might impact upon the US. This week GDP revisions strengthened the chance of a rise in the rate some time before Christmas.

事實上，令人吃驚的是，美國的貨幣政策幾乎從未直接關注過美元的全球流動角色。仔細閱讀美聯儲聲明或美聯儲主席珍妮特耶倫近期的言論，你會很難找到太多提及美國境外世界的語句。耶倫十分關注數據，但她關注的都是美國國內數據：失業率、通脹率和GDP。只有在可能影響美國的情況下，全球經濟纔會得到重視。本週美國對GDP的修正，提高了在聖誕節前某個時候加息的可能性。

One might expect the Fed to worry more about the strength of its currency, particularly given evidence it has hit the profits of US foreign subsidiaries. But the US is a fundamentally closed economy where domestic demand conditions outweigh those from overseas. Instead, if anyone is worried about the effect of a strong dollar, it is the IMF, which recently warned of “significant and abrupt rebalancing of international portfolios” should the Fed raise rates. A further reason for the dollar’s strength is confirmation of a lack of credible alternatives. Those Cassandras fretting about how monetary ease damages the dollar’s reserve currency status fail to appreciate how this is built not on its strength but its depth. Dollar assets are pervasive and easily sold.

有人可能會預計，美聯儲對美元走強更擔心一些，尤其是有證據表明美元走強已傷及美國駐外分公司的盈利。但是，美國從根本上說是一個封閉經濟體，其國內需求狀況的重要性壓倒了來自境外的需求。相反，如果說有誰擔心強勢美元的影響，那就是IMF。最近，IMF曾警告說，一旦美聯儲加息，“國際組合資產將發生大幅度、突然的再平衡”。美元走強的一個深層次原因，是人們確信美元缺乏可靠的替代品。那些預言寬鬆貨幣政策會毀了美元儲備貨幣地位的預言家們，未能認識到美元的這種地位並不是建立在其強勢匯率上，而是建立在其深入滲透上。美元資產無處不在，能夠輕而易舉地拋售出手。

China’s efforts to prop up its stock market — including trading suspensions and printing renminbi to chase a market level — shows how far it has to go. Nor can the euro mount a challenge when the ECB appears politically hampered from dispensing cash in a crisis.

中國支撐股市的努力——包括爲追逐某一市場點位而停牌或印鈔，顯示了中國在不得已的情況下走了多遠。而歐洲央行(ECB)在危機中撒錢之舉似乎也遭遇了政治上的阻礙，這令歐元很難對美元構成挑戰

In the words of an influential monetary thinker, “never reason from a price change”. What matters is not a currency’s price, but the forces driving it. At present, the dollar is strong because the US is too. Notwithstanding the IMF’s concern, Ms Yellen’s disregard for conditions outside of the US is unlikely to budge. Nor should it. The next rise in US rates will be the most telegraphed in the Fed’s history. There will be no excuse for a tantrum.

用一位很有影響力的貨幣思想家的話說，“永遠不要理性分析價格變動”。重要的不在於貨幣的匯率，而在於推動匯率波動的因素。目前，美元的強勢是由於美國經濟的強勢。儘管IMF對加息存在顧慮，耶倫無視美國以外狀況的態度不太可能改變，也不應該改變。美國下次加息，將成爲美聯儲歷史上傳達最充分的加息。對此，人們沒理由表示不滿。