Hong Kong’s dollar peg is tough. In its 30-plus years it has withstood landmark currency accords, two financial crises and Sars, not to mention perennial debate about its suitability. But the world’s longest-running, unchanged currency regime is facing a fresh challenge: its neighbour, the renminbi.

港元盯住美元的联系汇率制度相当稳固。在实行这一制度的30多年间，它不仅经受住了里程碑式货币协定、两次金融危机以及“非典”(SARS)的冲击，更经受住了年复一年的、关于这一制度是否合时宜的争论。但这个世界上实行时间最长、未曾发生过改变的汇率制度正面临新的挑战，这一挑战来自中国内地的人民币。

With data on Chinese capital flows slow to emerge, Hong Kong’s peg to the US dollar has become a gauge of just how much the August devaluation has unsettled investors.

由于中国资本流动数据不会很快出来，港元与美元的挂钩已成为衡量8月份人民币贬值在多大程度上引发了投资者不安的标尺。

Since that shock move the Hong Kong dollar has whipsawed within its narrow band versus its US counterpart. Initially speculation mounted that a weaker renminbi would force Hong Kong to devalue its currency, and this pushed it lower. Beijing’s still-tight control of its currency since the move, however, has eased that pressure.

自人民币意外贬值以来，港元兑美元汇率一直在狭窄区间内来回波动。最初，越来越多的猜测认为，人民币走弱将迫使香港当局让港元贬值，这种猜测一度推低了港元汇率。然而，北京方面此后对人民币汇率依旧严格的管控，缓解了港元面临的贬值压力。

Amid suspected outflows from China following the devaluation the Hong Kong Monetary Authority has intervened to defend the stronger end of the currency’s HK$7.75 to HK$7.78 range.

在人民币贬值后资本疑似流出中国的背景下，香港金融管理局(HKMA)对汇市实施了干预，以守卫1美元兑7.75港元至1美元兑至7.78港元的汇率区间强方。

The city-state’s peg is technically a currency board — its monetary base is fully backed by equivalent dollar reserves — and this has given it strong credibility in the markets. Defending strength involves selling local currency, which the HKMA can in theory do for ever.

香港的联系汇率制严格来说是一种货币局制度——其货币基础得到等值美元储备的全额支撑——因此这种制度在市场上拥有很强的可信度。守卫汇率区间强方涉及的是卖出本币，这种情况下，香港金管局理论上拥有无限的弹药。

“A lot of people got that wrong,” says Mitul Kotecha, head of Asia currency and rates strategy at Barclays. “They first looked for what was exposed and saw the Hong Kong dollar. But what was really unappreciated was where flows into China were coming from — which was Hong Kong — and how those could reverse.”

“很多人都搞错了。”巴克莱(Barclays)亚洲外汇与利率策略主管米图尔科特查(Mitul Kotecha)说，“他们首先寻找哪些货币受到冲击，然后发现了港元。但他们根本没意识到流入中国的资金来自哪里——是来自香港——以及这些资金会如何撤退。”

Figures for deposits in Hong Kong during August are due this week and will be scrutinised for any signs of a shift between those in renminbi — about 10 per cent of the total — and local currency. Not all the renminbi deposits are from the mainland; many local savers hold funds in both currencies, largely to bet on renminbi appreciation.

香港8月的存款数据将在本周发布，届时市场将仔细研读这些数据，以寻找一切关于人民币存款（占香港存款总额的10%）与港元存款发生转换的迹象。并非所有的人民币存款都来自中国内地；许多香港储户都持有这两种货币的资金，主要是为了押注人民币升值。

“People are assuming renminbi deposits will have gone down, although August might be too soon to show this,” says one strategist.

“人们正预期人民币存款减少了，尽管8月的数据可能还呈现不出这一趋势，”一名策略师说。

The HKMA has already hinted that there has been a shift. In its half-yearly review last week, the authority noted that its undertaking to buy dollars at HK$7.75 had been triggered “multiple times” this month, “possibly because of asset reallocations following the renminbi depreciation”.

香港金管局已暗示变化已经发生。在上周发布的半年度报告中，该局指出，其以1美元兑7.75港元的汇率购买美元的保证（强方兑换保证——译者注）本月已“多次”被触发，“可能的原因是人民币贬值后出现了资产重新配置”。

Hong Kong’s peg has over time made it a haven for various flows of capital seeking a dollar proxy or at least a staging post. Last summer it was Russia’s turn, when rising tensions with the US and a weakening rouble prompted companies to move funds to Hong Kong.

多年来，联系汇率制已使香港成为寻找美元“替身”（或至少是寻找中转站）的各式资本流动的避风港。去年夏天那波行情是俄罗斯引发的，当时俄美紧张关系的升级以及卢布的不断贬值促使俄罗斯企业将资金转移至香港。

The peg’s current period of upward pressure is, at 23 days and counting, its longest since December 2012. At that time the peg was being buffeted by a flood of US dollars from investors who, bolstered by quantitative easing, were seeking higher-yielding investments in the region.

港元与美元的挂钩面临的这一波上行压力（目前已进入第23天，且还在持续）是自2012年12月以来持续时间最长的。彼时，香港的联系汇率制受到美元大量涌入造成的冲击，这些美元来自在美国量化宽松政策支撑下到这一地区寻找更高投资回报的投资者。