人民幣已成為全球第四大支付貨幣，緊隨美元、歐元和英鎊。

之前，中國央行曾經就是否明確承諾取消資本管制，而進行過探討。這些管制措施使得人民幣不能按市場確定的價格與其他貨幣自由兌換。

如是種種是否意味著人民幣終于要進入全盛時代呢？很難這樣說。

人們將發現，和媒體報道相比，上述現象以及人民幣成為國際貨幣基金組織（IMF）官方儲備貨幣的消息并沒有那么大的影響。

小巫見大巫

人民幣在全球支付中占的比重仍很小。確切地說，2015年9月份這個數字為2.45%，8月份的數值略高一些，為2.79%，居全球第四位。這還不到英鎊所占比重（9%）的三分之一，歐元占比（29%）的十分之一，和美元的份額（43%）相比更是小巫見大巫。

要衡量一種貨幣在國際上的普及程度，另一個指標是外匯儲備占比，它是國際貿易順差積累的結果。

盡管中國和美國在世界貿易中所占的比重相當（約12%），但人民幣在其他國家/地區的外匯儲備中只占1%，美元則占64%。

換句話說，人民幣在國際支付和外匯儲備中的比重并不像中國在世界貿易中的份量那么重；同樣的，美元在這方面的占比則超過了美國在世界貿易中的比重，原因是美國資本市場規模龐大、流動性強而且安全，廣受投資者和政府青睞。

單從市場力量的角度判斷，人民幣的份量應該逐漸加重，美元占比則應逐步下降。

在貿易和投資中，收付款雙方使用同一種貨幣可以降低交易成本、貨幣風險和潛在波動。因此，隨著和中國貿易往來的增加，想使用人民幣的人就會增多。

開始遠離貿易

今后，中國在全球GDP中的比重（2014年名義占比為13.3%）很可能上升，原因是中國經濟增速仍高于其他大型經濟體的平均水平。但人民幣在國際支付和外匯儲備中的普及率可能上升的較慢，原因是中國正在遠離以貿易為動力的經濟發展模式。

出現這種情況是因為中國打算減少對出口拉動型增長的依賴，并提高國內消費在GDP中的占比（目前這個比值非常低）。

盡管到目前為止幾乎還沒有跡象表明正在出現這種局面，但如果在這方面取得成功，那就意味著貿易占中國GDP的比重將減輕，也可能意味著人民幣得到更廣泛應用的速度將低于過去一段時間的水平。

成為儲備貨幣路途艱難

要真正成為IMF認可的官方儲備貨幣，中國必須滿足多項標準，從而使人民幣“可以自由使用”，也就是說，任何人在任何時候都可以買賣人民幣。

這些標準包括由市場決定的利率、匯率靈活性和貨幣可兌換性、更開放的資本項目以及在官方儲備、國際銀行債務和全球債務證券中占據相當大的份額。盡管中國已經為此采取了許多措施，而且最近還在這樣做，但就任何一條標準而言，中國距離完全達標都還有很大的差距。

這些標準都要求改革并放開國內金融市場，這樣做在政治和技術上都有難度。這些改革會削弱政府為了維持穩定和促進增長而制定政策的能力。這是因為國際金融領域存在“三元悖論”，也就是說，貨幣政策的三大目標——控制利率、保持匯率靈活性和資本流動性——在任何時候都只能同時實現兩個。

市場干預

中國政府2015年夏天面對金融市場劇烈波動而采取的措施表明，它尚未準備好實施或完成諸多必須的改革。

對市場的干預表明中國政府還不愿意讓市場力量來主導人民幣和金融市場。這些干預行動包括對估值偏高的股市的暴跌進行遏制，以及用20年來前所未見的力度下調人民幣中間價。說到股市，政府也曾助推此前的A股泡沫。

信任要自己爭取

如今，IMF已經把人民幣指定為儲備貨幣，但這并不意味著人民幣將迅速而且廣泛地發揮儲備貨幣功能。只有建立了對貨幣的信心，各國央行和個人投資者才會使用或持有人民幣。

要做到這一點，中國金融市場就必須在深度、多元性、透明度和安全性方面達到美國的水平，美元正是藉此保持著全球最受歡迎儲備貨幣的地位，并未受到美國在全球貿易和投資中占比下降的影響。

如果某種貨幣受政治因素主導，而不是由市場力量左右，其他政府就不愿將其納入外匯儲備，這可以理解。

市場參與者的信任，必然是靠日積月累贏得的，僅憑IMF這樣的國際機構授權無法做到這一點。

利與弊

對于一種貨幣來說，只有當它在國際貨幣體系中得到了更廣泛地應用，或者說實現了國際化，才會帶來一系列好處。

其中之一是鑄幣紅利，也就是貨幣發行國因貨幣價值高于鑄幣成本而得到的收益。其他好處還包括貨幣政策更寬松（更能促進增長），從而使經濟發展速度有所加快，以及可以用本幣進行國際借貸和投資，從而避免貨幣風險。

但也會出現一些不利影響，比如失去對貨幣政策有效性的控制，以及讓國內經濟暴露在不穩定（而且波動越發劇烈）的全球資本流動面前。

正是出于這個原因，本幣頗受國際投資者青睞的小型開放經濟體，如新加坡和瑞士，長期以來一直拒絕國際化。相反，中國似乎認為人民幣成為儲備貨幣對自己有利，而且這樣的“地位”代表著中國希望贏得的威信。

長期而言，人民幣在國際上得到更廣泛的使用將使中國和世界經濟同時受益。中國將受益于國際化所需的國內金融市場改革，世界其他地區則會在貿易支付、投資和貨幣儲備方面得到一個更多元化的貨幣籃子，從而改變目前過度依賴美元的局面。

這應該還有助于避免各國之間出現長期而且過大的貿易和金融不平衡。

但在此之前，中國需要對國內金融體系實施重大改革，這項工作不會進展的很快，也不會容易，更不會有完全的把握。（財富中文網）

琳達?利姆是密歇根大學戰略學教授。本文最初刊登在網站theconversation.com上。

譯者：Charlie

校對：詹妮

China’s currency, the yuan, became the world’s fourth-most-used form of payment, behind the U.S. dollar, euro and pound sterling, having (marginally) pushed past the Japanese yen.

China’s central bank discussed whether to make an explicit pledge to dismantle the capital controls that prevent the yuan from becoming fully convertible with other currencies at rates determined by the market.

Does all this mean the yuan’s heyday has finally arrived? Hardly.

As we will see, there is less significance to this phenomenon — and talk of the yuan becoming an “official IMF reserve currency” — than media headlines suggest.

A drop in the bucket

The yuan still accounts for a small fraction of world payments, 2.45%, to be precise in September after edging up to 2.79% — and fourth place — a month earlier. This is less than a third of the pound’s 9% share, a tenth of the euro’s 29% and a drop in the bucket of the dollar’s 43%.

Another measure of a currency’s international prevalence is in foreign exchange reserves, which result from the accumulation of export surpluses.

The yuan accounts for just 1% of other countries’ allocated reserves, compared with 64% for the dollar, even though China accounts for the same share of world trade (about 12%) as the U.S.

In other words, the yuan is underrepresented in payments and reserves relative to its share of world trade, while the dollar is similarly overrepresented, due to the popularity among investors and governments of the U.S.’ broad, liquid and secure capital markets.

Market forces alone should lead one to expect the yuan’s share to rise and the dollar’s to fall over time.

Matching the currency used in payments and receipts in trade and investment reduces transaction costs, currency risk and volatility exposure, so more people will want to use the yuan as their transactions with China increase.

A shift away from trade

China’s share of world GDP (13.3% in nominal terms as of 2014) will likely rise as its economy continues to outpace the average of other large economies. But use of the yuan for payments and reserves may increase at a slower pace as China shifts away from an economy fueled by trade.

This is because China plans to reduce its reliance on export-led growth and increase domestic consumption as a share of GDP (which is currently very low).

Though there are few signs of this happening so far, the plan, if successful, means that trade as a share of GDP will begin to shrink. And that will likely mean slower growth in use of the yuan than in the recent past.

The difficult road to becoming a reserve currency

To become an “official” IMF-endorsed “reserve currency,” China has to meet various criteria that would make the yuan “freely usable”: that is, readily bought and sold by anyone at any time.

These criteria include a market-determined interest rate, exchange rate flexibility and convertibility, a more open capital account, and a significant share of official reserves, international banking liabilities and global debt securities. While many steps have been taken in these directions, including very recently, none of these criteria is close to being fully achieved.

All this requires politically and technically difficult domestic financial market reforms and liberalization. Such reforms reduce the government’s ability to establish policies that reduce volatility and encourage growth. That’s because of what is known as the “trilemma” of international finance, in which only two of the three goals of monetary policy — control of interest rates, exchange rate flexibility and capital mobility – can be achieved at the same time.

Market manipulations

The Chinese government’s own reactions to this past summer’s financial market turmoil suggest that it is not ready to undertake or complete many of the required reforms.

Its interventions show that it is not yet willing to allow market forces to rule in its currency and financial markets. This includes its effort to halt the precipitous decline of an overvalued stock market — which it itself had previously boosted — and to devalue the yuan by the largest amount in two decades.

Trust must be earned

Now，IMF designated the yuan as a reserve currency, this does not mean that its use as such will rise quickly or greatly. World central banks and individual investors will only increase their use and holdings of yuan if they have confidence in the currency.

And that won’t happen until Chinese financial markets develop the depth, diversity, transparency and security that have kept the dollar reigning supreme as the world’s preferred reserve currency, even as the U.S. share of global trade and investment has declined.

Governments are understandably reluctant to hold reserves in a politically managed rather than market-determined currency.

The trust of market actors has to be earned over time and cannot be merely conferred by an international body like the IMF.

Benefits and disadvantages

There are some benefits when a currency becomes more widely used in the global monetary system — its “internationalization”.

One benefit is “seignorage,” which is the revenue the issuer gets from the value of a currency over and above the cost of producing it. Others include a looser (more stimulative) monetary policy, enabling (marginally) faster growth, and the ability to borrow and invest internationally in one’s own currency, thus avoiding currency risk.

But there are also disadvantages, including losing control over the effectiveness of monetary policy and exposing the domestic economy to destabilizing (and increasingly volatile) global capital flows.

This is why small open economies like Singapore and Switzerland, whose currencies are popular with international investors, have long resisted internationalization. In contrast, China seems to regard reserve currency status as desirable for its own sake, as a “status good” conferring an assumed prestige that it craves.

In the longer run, both China and the world economy stand to gain from increased international use of the yuan. China will benefit from the domestic financial market reforms that internationalization will require, and the rest of the world will get a more diverse basket of currencies to choose from to finance trade and investment and hold reserves, reducing the current overdependence on the U.S. dollar.

This should also help us avoid the chronic and excessive trade and financial imbalances among countries.

But before we can get there, China needs to follow through on major reforms of its domestic financial system, which will not be quick, easy or certain.

Linda Lim is a professor of strategy at the University of Michigan. This piece was originally published on The Conversation.