Vietnam's currency is consistently falling below the official exchange rates, creating a thriving black market for gold and dollars.

越南盾已跌破官方汇率，仍在不断下滑，并使得黄金和黑市美元蓬勃发展。

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The Official exchange rates as of December 2001 were 1 Euro (EUR) = won 2.81; 1 UK pound (GBP) = won 4.14; and 1 US dollar (USD) = won 2.16

2001年12月的官方汇率为1欧元（EUR）＝2.81圆；1英镑（GBP）＝4.14圆；1美元（USD）＝2.16圆。

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Such transfer shall be effected promptly on the basis of official exchange rates or where there are no official exchange rates, at the prevailing foreign exchange market rates for current payment.

此种汇出应在正式比价的基础上，或在没有正式比价时按当时支付的有效外汇市场比价迅速办理。

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They charge up to ten times more than informal channels, must change money at official rates and, in some countries, levy a tax on the exchange.

FORBES: Magazine Article