最近，國際貨幣基金組織（IMF）主席拉加德明確宣布支持工作人員將人民幣納入特別提款權（SDR）籃子的建議之后，市場一致認為人民幣成為儲備貨幣已指日可待。作為一種記賬單位，特別提款權的作用是穩定貨幣匯率。雖然它只是高深莫測的國際貨幣交易體系的一部分，但這可是一條重大新聞。

要成為儲備貨幣既不像看上去那么簡單，也不像表面上那么復雜。說它復雜是因為這是一場政治較力，一方是在全球經濟領域處于優勢地位的中國，另一方則是主導各個國際組織的美國。說它簡單的原因是成為IMF儲備貨幣后，人民幣在世界經濟中發揮的作用可能較小。

表面上看，IMF未采取任何行動是為了“確保特別提款權相關業務的順利進行”，并在何時調整的問題上考慮到了特別提款權使用國的反饋。這種說辭有些言不由衷，因為繼續使用目前的四種儲備貨幣，也就是美元、日元、歐元和英鎊，并不會帶來任何干擾。顯然，所有這一切都和人民幣有關。鑒于人民幣的價值和流動性尚不明朗，在塵埃落定前使用“拖字訣”是謹慎的做法。

IMF表面上有一套選擇儲備貨幣的客觀程序。第一條評判標準是用某種貨幣結算的國際貿易額。IMF規定，合格貨幣“由成員國或貨幣聯盟發行，并在全球經濟中發揮核心作用。”用人民幣結算的國際貿易額占全球貿易總額的2.8%（2015年8月），在所有貨幣中排名第四。因此，在這方面人民幣無疑是合格的。

第二條標準是這種貨幣必須“可以自由使用”。雖然IMF章程就此進行了說明，但在這一點上仍可做出多種解釋，而這就是爭議所在。要進入儲備貨幣籃子，某種貨幣必須在特別提款權使用國穩定自身貨幣的過程中發揮作用。采用固定匯率制、有管理的浮動匯率制或者自由浮動匯率制的國家都可能符合這條標準，實施有限資本管制的國家也是如此。顯然，有些貨幣未達到這項要求，但“自由使用”和非自由使用貨幣之間的界限最多也只能說是模糊不清。

客觀上講，這個問題很難解決，原因是成為儲備貨幣會改變對某種貨幣的需求。同樣的，非儲備貨幣身份也許會影響持有某種貨幣的意愿。對于當前和今后IMF成員國為調整外匯儲備而產生的人民幣需求量，人們可以探討這項數據是否支持人民幣進入儲備貨幣籃子；但說到底，這樣的討論既依賴于經濟證據，也取決于政治風向，二者的影響不相上下。

如果把人民幣納入儲備貨幣籃子，但事后發現它并不符合“自由使用”標準，就會出現“請神容易送神難”的局面。如果一些國家由于擔心流動性或者今后的匯率而不愿持有人民幣，發生匯兌危機時，儲備貨幣中含有人民幣（使用國必須接受整個貨幣籃子）就會降低特別提款權在提供流動性方面的效率。不過，人民幣在這個貨幣籃子中的百分比將較小，它對特別提款權效率的影響也許可以忽略不計。

今年12月份，IMF將作出重大決定，那就是基于中國和大多數國家的貿易關系、中國巨大的經濟體量以及主要貿易國地位來判斷讓人民幣在儲備貨幣籃子中獲得一席之地是件好事，還是說人民幣成為儲備貨幣的條件尚未成熟。目前來看，這兩種選擇在政治層面上都會有影響。就像中國發起設立的亞洲基礎設施投資銀行表明的那樣，這樣的選擇將影響到國際匯兌制度框架。

或者，IMF也許還可以通過建立另一種儲備貨幣籃子調整機制來解決這個難題，具體做法是設立第一特別提款權（SDR1），并沿用現有儲備貨幣籃子，只是可能基于某些標準來改變各儲備貨幣所占的比例；同時設立第二特別提款權（SDR2），其中囊括一些新的貨幣。IMF可以把人民幣納入SDR2的首個貨幣籃子之中。在一定時間段內，這兩個貨幣籃子可以同時存在。如果使用國的偏好表明SDR2優于SDR1，前者實際上就會取代后者。

在進行下一次階段性評估時，更受歡迎的那種特別提款權就會成為SDR1，而且還可以根據屆時的環境來決定是否要設立新的SDR2。這樣的機制可以把政治屏蔽在儲備貨幣選擇程序之外，并讓市場來決定儲備貨幣籃子的構成。這樣一來，在這個問題上，就不會出現目前通過地緣政治手段來增強或削弱一國的威信和經濟實力，從而使另一國受益的情況。IMF應該盡可能地遠離政治，而特別提款權改革顯然正是朝著這個方向邁出的一步。（財富中文網）

杰瑞?尼克斯伯格是加州大學洛杉磯分校安德森管理學院經濟學兼職教授。

譯者：Charlie

Earlier this fall, the IMF postponed a scheduled update of the designated basket of reserve currencies, a basket that is used by member countries for Special Drawing Rights (SDR). Though SDR’s, a form of borrowing for purposes of currency stabilization, are part of the arcane mechanism of international currency transactions, this was big news. It was seen as a rebuff of China in the wake of last summer’s intervention in the Shanghai Stock Exchange and devaluation of the Chinese Yuan. However, being a reserve currency is both more and less than meets the eye. The more is the political struggle between Chinese ascendency in the world economy and US dominance in international organizations. The less is the relatively minor role that the yuan as an IMF-designated reserve currency would play in the world economy.

The ostensible reason for the IMF inaction was to “ensure the smooth functioning of SDR-related operations,” and to respond to SDR users feedback on the timing of any changes. This is a bit disingenuous as a continuation of the current four currencies; the US dollar, Japanese Yen, Euro, and UK Pound Sterling, would not have caused disruption. Clearly it is all about the yuan. At a time when the yuan’s value and liquidity were uncertain, a postponement until the dust settled was prudent.

The IMF ostensibly has an objective process for being designated a reserve currency. The first criterion is based on the volume of international transactions cleared in the currency. The IMF specifies that currencies qualifying are those “issued by members or currency unions that play a central role in the global economy.” The yuan is fourth among currencies used in transactions at 2.8% (August 2015). Thus, there is no doubt on this basis it qualifies.

The second is that currencies must be “freely usable.” While there are clarifying statements in the IMF Charter, they are subject to interpretation. Herein is the crux of the debate. To be part of the market basket of currencies, each currency has to be useful to those who borrow SDR’s to stabilize fluctuations in their own currency. A country with a fixed, managed float or freely floating exchange rate may qualify as may one with limited capital controls. It is clear that some currencies do not meet the definition, but the dividing line between those that are “freely usable” and those that are not is fuzzy at best.

This is a difficult nut to crack objectively because the designation of “reserve currency,” changes the demand for that currency. As well, not being a reserve currency might be a disincentive for holding the same currency. One can argue whether the data on the current and future demand for the yuan as a useful currency for members’ foreign exchange portfolios support inclusion or not, but in the end the discussion is based on political perspective as much as economic evidence.

The consequence of designating the yuan as a reserve currency if in fact it does not ex-post meet the criteria of “freely usable” is that once in, removal is difficult. If countries do not want to hold the yuan due to concerns about its liquidity or concerns about its future value, then its presence in the basket of currencies (one has to take the entire basket) will make SDR’s a less efficient mechanism for providing liquidity in the event of an exchange crisis. However, the yuan’s percentage of the basket will be relatively small and this efficiency cost might be negligible.

In December, the IMF will make a leap of faith and decide that either because China has trading relations with most countries, has a large economy, and is a major trading economy, having the Chinese yuan as a small part of the basket would be a good thing, or that the conditions are not yet ripe for the yuan to be in the SDR basket of reserve currencies. Either choice currently has political implications, and as the Chinese-sponsored Asian Insfrastructure Investment Bank demonstrated, implications for the institutional framework for international exchange.

Alternatively, the IMF could cut the Gordian Knot with a mechanism to decide changes in the basket of currencies by having an SDR1, which maintains the old basket, perhaps with changes in the percentages based on some criteria, and an SDR2, which includes some new currency(ies). The first SDR2 basket would contain the yuan. These baskets can run parallel for a set period of time. Based on the preferences of countries using SDR’s, SDR2 would, if better than SDR1, replace SDR1 de facto.

At the next periodic evaluation, the more popular of SDR1 and SDR2 would then become SDR1 and the environment of the day would determine if a new SDR2 be created. Such a mechanism would take the politics out of reserve currency determination and let the market decide the basket. The current geopolitical maneuvering to enhance or diminish the prestige and economic power of one country in favor of another would not enter the equation. The IMF ought to be as apolitical as possible, and a reform of the SDR is an obvious step in that direction.

Jerry Nickelsburg is an adjunct professor of economics at UCLA’s Anderson School of Management.