2015年8月11日，中国人民银行将美元对人民币汇率的日常中间价提高了1.9%，从而导致人民币对美元有效贬值1.8%，创下2005年7月人民银行决定人民币不再盯住美元以来的最大单日贬值纪录。与此同时，中国人民银行还宣布，即日起人民币对美元的每日固定汇率将参考上一交易日的收盘价，以及外汇市场的供求状况和全球主要货币的走势。简言之，中国央行开始让人民币汇率更多地由市场决定，而近期市场恰恰认为人民币应该下跌。

研究中国问题的人士和主流媒体对此展开了热烈讨论：到底发生了什么事？为什么在这个时候发生？北京是通过货币竞争性贬值扶持萎靡不振的出口部门，还是期待人民币被纳入国际货币基金组织（IMF）特别提款权（SDR）而开始推进汇率自由化？

自由下滑

人民币这回一次性贬值的主要催化剂，很可能是IMF此前一周发表的一份声明。IMF认为，由于人民币的重要基本指标仍然落后于世界其他主要货币，它可能推迟对人民币纳入特别提款权的评估。为此，中国人民银行抓紧推行计划中的人民币汇率改革，而这次改革的基础在两个星期之前就已经备妥。就在7月24日星期五，中国国务院宣布将进一步扩大人民币汇率的双向浮动范围。可以肯定的是，推出汇率改革也是中国人民银行政治上的考虑，因为它最可能的结果是导致人民币汇率下跌，这将支持经济的增长。7月份，中国商品出口额按美元计算比去年同期下降了8.3%，显示净出口不再像2015年上半年那样，能够为国内生产总值的增长提供支持。

8月11日的一次性贬值，只是让人民币每日固定汇率更加市场化的第一步。过去几个月里，人民币对美元即期汇率一直趋向于接近人民币交易区间的弱势端，与此同时，中国人民银行一直保持每日固定汇率不变。这导致人民币在过去一年里对其他货币升值约10%-15%。

当然，对于人民币来说，即使贬值3%也算是大动作。今年人民币最大波动幅度是0.16%，这与其他货币相比简直是小巫见大巫。过去一年，欧元对美元贬值18%，日元对美元贬值22%。而且，人民币过去18个月里几乎对所有货币都在升值。到目前为止，它依然对欧元升值约20%，对日元升值15%，对韩元升值10%。

那么，现在是什么情况呢？8月12日人民币又贬值了1.6%，这可能预示着，在中国人民银行的引导下，人民币汇率正形成一种混合的市场导向模式。12日，由于市场强烈预期人民币会进一步贬值，人民币对美元汇率出现下跌，但有报道称，在交易最后时段中国人民银行进行了干预，它指示国有银行抛出美元，结果人民币对美元汇率在交易最后几分钟上涨了大约1%，从而使周一（8月10日）以来的贬值幅度缩小到2.8%。

就市场而言，人民币面临的风险是出现自我完成式螺旋贬值。由于经济增速减缓、资本流出加速以及受到通缩压力，如今市场情绪已经达到负面。而政府在股市上救市失策，也没有激发人们的信心。所以，中国人民银行不太可能把人民币完全交给市场。中国官员已经表示，人民币与经济基本面已经更趋一致。这暗示人民币对美元继续贬值的程度将是有限的。北京的真正目的到底是什么，接下来的几个星期将成为重要的指示器。如果是大幅度贬值，那么出口会得到刺激。如果是中等幅度贬值，那么人民币不仅对美元，而且对一揽子货币的比价都会得到修正。

当心你的期望

长期以来，中国的国际贸易伙伴一直在劝说北京让人民币汇率自由浮动。全球金融危机发生后，这一呼声更为强烈。美国议员们估计，中国一直在人为压低人民币汇率，以便使出口品在全球保持廉价。为此，他们预期人民币在实现自由浮动后会对美元升值，而美国则恢复出口竞争力。对汇率操纵问题，华盛顿一直在进行辩论，但现在辩论比过去少了许多。IMF曾经表示，人民币已经不存在估值过低问题。由于贸易数据疲软，此刻让人民币更自由地浮动，可能对中国有利，但却让美国不舒服，因为这样一来美联储9月份的加息预期就需要重新考虑。

北京会限制人民币贬值幅度的另一个原因是，如果贬值速度太快、幅度太大，那就会进一步加剧中国与美国及其他贸易伙伴的紧张关系。北京没有必要在习近平主席将要会见奥巴马总统之前一个月，为美中双边议程再添加一个有争议的议题。另外，尽管IMF欢迎中国人民银行决定让人民币汇率自由浮动，并暗示它将更积极地考虑将人民币纳入特别提款权，但美国的议员们现在又把汇率操纵问题摆上台面，并声称由于汇率操纵，人民币没有资格被纳入特别提款权。因此，如果人民币持续贬值，奥巴马政府要想支持人民币加入特别提款权就会面临政治困难。

接下来的几个星期十分关键。最大的可能是，北京所选择的时机，是要赶在9月美中峰会到来之前，尤其是11月IMF作出决定前，让人民币汇率找到自己的底部。中国人民银行下个月要维持微妙的平衡，要显示出它允许人民币汇率更加自由地浮动，而不是朝某个方向给人民币施压。

On August 11th, 2015, the People's Bank of China (PBoC), lifted the daily fixing rate for the USD-CNY exchange rate by 1.9%, leading to an effective 1.8% RMB devaluation, the biggest one day move since July 2005, when the PBoC de-pegged the RMB from the US dollar. At the same time, the PBoC also announced that from now on, the daily fixing rate for the RMB-USD will be made with a reference to the previous day's closing rate, and by taking into account FX market supply-demand and major global currency movements. Put simply, the PBoC moved to make the Chinese currency more market-determined, and right now the market determines that it should be weaker.

Debate in China-watching circles and the mainstream media has been heated: What just happened and why did it happen now? Is Beijing engaging in competitive devaluation aimed at boosting its ailing export sector or is it moving decidedly forward with currency liberalization, as it hopes to see the RMB included in the IMF's special drawing rights (SDR)?

Free falling

The main catalyst for the one-off depreciation was most probably the IMF statement the previous week, when the IMF concluded that the RMB trails its global counterparts in major benchmarks and suggested that review of the RMB's inclusion in the Special Drawing Rights (SDR) mechanism could be delayed. This prompted the PBoC to push forward planned reforms of the currency. The groundwork for such reform was already laid two weeks prior, when on Friday, July 24, the State Council announced its intention to further expand the two-way floating range of the exchange rate. To be sure, it was also politically expedient for the PBoC to launch the reform of the exchange rate when the most likely outcome—a weaker currency—could also support growth. Merchandise exports slumped on a US–dollar basis by 8.3% year on year in July, suggesting that net exports can no longer offer much support to GDP expansion going forward as they did in the first half of 2015.

The one-off devaluation on August 11 was therefore a first step in aligning the daily fixing more closely with the market. The CNY-USD spot exchange rates have gravitated to the weak end of the RMB's trading band for several months while the PBoC kept the daily fixing rates steady. This has led the RMB to rise against other currencies, by an estimated 10%-15% over the past year.

Indeed, even though a 3% depreciation is an enormous move for the RMB—its largest move this year has been 0.16%—it pales in comparison with other currencies: Over the past year, the euro has fallen by 18% against the US dollar while the Japanese yen has dropped by 22%. Moreover, the RMB has appreciated markedly against almost every currency over the last 18 months: it is still up around 20% against the Euro, 15% against the Yen and 10% against the South Korean Won.

So what now? The 1.6% depreciation on August 12 is probably a taste of things to come: a hybrid model of a market-oriented exchange rate, steered in the right direction by the PBoC. During the course of the day, the RMB fell against the USD given strong market expectations of further depreciation. But the PBoC reportedly intervened in the final minutes of trading, instructing state-owned banks to sell dollars on its behalf. As a result, the RMB gained roughly 1% against the USD in the last few minutes of trading, bringing it down 2.8% since Monday.

Left to the market's devices, the RMB risks going down a self-fulfilling depreciation spiral: Market sentiment is already negative due to economic slowdown, rising capital outflows and deflationary pressure. And the government mishandling the stock market bailout hasn't inspired confidence either. So the PBoC is unlikely to leave the RMB completely to the market's devices. Chinese officials have already indicated that the currency is now more aligned with economic fundamentals, suggesting that a further weakening of the RMB against the USD will be limited. The next few weeks will be important indicators of what Beijing is truly aiming for: A deep depreciation that will boost exports, or a modest devaluation that will correct itself as the RMB moves against a basket of currencies, rather than against the US dollar alone.

Careful what you wish for

China's international trading partners have long lobbied Beijing to let the currency float freely. These calls were loudest after the global financial crisis, when US senators estimated that China was keeping the RMB artificially low in order to make its exports cheaper globally. As such, they hoped that by letting the RMB float freely, it would appreciate against the USD and restore US export competitiveness. While the currency manipulation debate still surfaces in Washington from time to time, it is now more muted than in the past. And the IMF has already said that the RMB is no longer undervalued. Letting the RMB float more freely now, is perhaps convenient for China in light of its weak trade data, but potentially very inconvenient for the US that might need to rethink the Fed's expected rate hike in September.

This is another reason for Beijing to limit the extent of RMB depreciation: A rapid and significant weakening would further exacerbate tensions with the United States and other trading partners. Beijing does not need another controversial item on the bilateral US-China agenda, one month before President Xi is planned to meet with President Obama. Furthermore, even though the IMF has welcomed the PBoC's decision to free the currency and has suggested that it viewed SDR inclusion more favourably, US senators are now raising the currency manipulation flag once again, arguing that this disqualifies the RMB from SDR inclusion. A further weakening of the RMB would make it politically difficult for the Obama Administration to support the RMB's inclusion in the SDR.

The next few weeks will therefore be key. Most probably, Beijing timed the move to allow the RMB time to find its feet before the September summit, and more importantly, before the IMF review in November. The PBoC has a delicate balancing act over the next month: It must show that it is allowing the RMB to float more freely, without nudging it too forcefully in the right direction.