8月11日，中國人民銀行宣布未來做市商向它提供的報價應基於前一日市場收盤價。與此同時，人民銀行將人民幣兌美元中間價下調1.9%。

這次貶值給全世界帶來衝擊。許多外國評論家擔心中國人民銀行讓人民幣貶值是為了提振中國的出口，從而引發新一輪貨幣戰。

這種擔心可以理解，但沒有必要。就像中國人民銀行副行長易綱所說：“我們無需靠人民幣貶值來促進出口。”有許多理由可以相信這一點。首先，中國很清楚貨幣戰爭是搬起石頭砸自己的腳。亞洲金融危機期間，中國經濟狀況更糟，但中國政府抵制住了人民幣貶值的誘惑。雖然沒有採取貶值手段，中國仍然毫髮無損地渡過了危機。其次，中國正努力將增長模式從投資－出口驅動向消費驅動轉變。中國仍有巨額貿易盈餘，貿易盈餘不斷下降給經濟帶來的消極影響，可以而且應該由國內需求特別是國內消費需求的增加來抵消。第三，作為世界最大貿易國，中國在全球出口所佔的份額已經超過12%，繼續擴大這一份額很難不導致貿易條件的惡化。第四，由於中國在加工貿易和全球生產價值鏈中的特殊地位，很難說人民幣貶值會對中國貿易盈餘的增加有什麼效果。最後，中國不僅是貿易國，也有巨額海外金融資產和負債，中國非金融公司的海外借款高達1萬億美元。人民幣任何大幅度貶值都將相應地增加中國企業的人民幣債務負擔，從而導致大量破產和不良貸款急劇增加。因此，避免捲入競爭性貶值不僅是作為主要大國的中國的責任，也符合中國自己的利益。

在我看來，中國人民銀行8月11日採取行動的背後有雙重目的。一是放寬中國人民銀行對人民幣匯率的控制，以便讓市場在人民幣匯率的決定中發揮更大作用。二是縮小官方匯率與反映市場供求的匯率之間的差距，以便匯率機制改革更加順利。世紀之交以來，美國和其他主要工業國一直敦促中國讓市場來決定人民幣的匯率機制。當中國朝這個方向努力，但最終結果是人民幣貶值的時候，它們的抱怨合理嗎？

出於種種原因，現在中國比任何時候都希望進行這樣的改革。8月11日人民幣的貶值，是中國姍姍來遲的匯率制度改革的一個重要里程碑。但我認為，由於事實上人民幣貶值壓力很大，如果中國人民銀行不加干涉地由做市商決定人民幣中間價，計劃中的一次性匯率調整就可能變成崩盤，而這一前景不是中國人民銀行希望見到的。結果，僅僅試水兩天之後，中國人民銀行就後退，並告訴市場人民幣只貶值3%，不會更多。市場也認為如此。之後人民幣匯率適度反彈，市場回歸平靜。

8月11日的插曲已經結束，但8月11日到13日人民幣匯率的大幅下跌表明，人民幣單向升值時代已經結束。未來，由於中國資本賬戶自由化和人民幣國際化，人民幣匯率將更為波動。由於中國經濟增長持續疲軟，中國人民銀行很可能會進一步放寬貨幣政策。與此同時，美聯儲將逐步退出量化寬鬆。這樣，在可預見的將來，人民幣貶值的可能性要大過升值。

如何讓市場決定人民幣匯率的同時防止貶值失控，是對中國貨幣決策者的嚴峻挑戰。對世界其他國家來說，如何在鼓勵中國放鬆對人民幣匯率管制的同時平靜地看待人民幣貶值，同樣也是一個嚴峻挑戰。希望雙方都經得起考驗。

On August 11, the People's Bank of China (PBOC) announced that in future the offer prices reported to it by market makers should be based on the closing parity rate of the market on the previous day. At the same time, the PBOC lowered the central parity rate by 1.9 per cent.

The depreciation sent a shockwave around the globe. Many foreign commentators feared that the PBOC has embarked on a course of devaluation to boost China's exports, which in turn would set off a new round of currency war.

This worry is understandable but unwarranted. As pointed out by the vice-governor of the PBOC, Yi Gang, “We do not need to devalue the RMB to promote exports.” There are many reasons to believe this is true. First, China knows well that currency wars are self-defeating. During the Asian Financial Crisis, China's economic situation was much worse, but China resisted the temptation to devalue the RMB. Even without resorting to devaluation, China was able to come out of the crisis unscathed. Second, China is very serious about shifting the growth mode from investment-export driven to domestic consumption driven. China is still running large trade surplus, the negative impact of a further narrowing in trade surplus on the economy can and should be offset by increase in domestic demand in general and domestic consumption in particular. Third, as the largest trade nation in the world, China's share of exports in global exports has already surpassed 12 per cent. It will be very difficult indeed for China to expand its share further without worsening its terms of trade greatly. Fourth, due to China's special position in processing trade and global value chain of production, it is difficult to assess how effective the devaluation will be in increasing China's trade surplus. Finally, China is not only a trading nation but also a nation with huge overseas financial assets and liabilities. Chinese nonfinancial corporations' foreign borrowing can be as high as 1 trillion USD. Any large devaluation will correspondingly increase the Chinese firms' debt burden in RMB terms, which will lead to a large number of bankruptcies and dramatic increase in nonperforming loans. Hence, to avoid getting involved in competitive devaluation is not only the responsibility of China as a major global power but also in its own self-interest.

In my view, the purpose behind the action taken on August 11 by the PBOC is twofold. First, to loosen PBOC's grip on the RMB exchange rate so as to allow the market to play a more important role in determining the exchange rate. Second, to narrow the gap between official exchange rate and the exchange rate implied by market demand and supply so as to make the reform of the exchange rate regime smoother. Since the turn of the century, the United States and other major industrial countries have been pushing China to allow the market to determine the RMB exchange-rate regime. When China made an effort towards that direction but ended up with RMB depreciation, it is legitimate for them to complain?

Now China is more willing than before to carry out such a reform for various reasons. The August 11 depreciation is an important landmark in China's long-overdue reform of its exchange-rate regime. However, I guess, due to the fact that the RMB depreciation pressure is too strong, if the PBOC let the market makers determine the central parity rate without intervention, the original planned one-off adjustment of the RMB exchange rate could morph into a rout, which is not a prospect the PBOC is ready to face. As a result, after testing the water just for two days, the PBOC retreated and told the market that the devaluation was just 3 percent and no more. Because the PBOC has enough ammunition to stabilize the exchange rate and the market also believes so, the exchange rate rebounded duly and calm returned to the market.

The August 11 episode has ended. However, the dramatic fall in the RMB exchange rate from August 11 to 13 August shows that the period of one-way appreciation of the RMB has ended. In the future, because of China's capital account liberalization and RMB internationalization, the RMB exchange rate will become more volatile. It is very likely that because growth of the Chinese economy will continue to be weak, the PBOC will have to loosen monetary policy further. At the same time, the US Fed will exit quantitative easing gradually. As a result, in the foreseeable future, the RMB is more likely to depreciate than to appreciate.

For the Chinese monetary authorities, how to allow the market to determine the RMB exchange rate while preventing the depreciation from sparking a rout is a serious challenge. For the rest of world, how to cheer China on to let go the RMB exchange rate while watching RMB depreciation in a quiet manner is an equally serious challenge. Hopefully, neither side will fail the tests.