exchange, i.e., foreign money, is really just another commodity to be bought and sold. This

如：外幣，只是一種可買賣的商品而已。

is where the term foreign exchange market comes from. It’s a market, so there must

這就是「外匯市場」的來由。它是一種市場，所以一定會有

be those who want to buy the currency, and those who supply it.

人想買外幣(需求者)，和賣外幣(供給者)。

On the demand side, what reason (or reasons) could people possibly have to want to purchase

以需求面而言，有什麼原因會讓人想持有外幣？

foreign exchange? Well, there are three major reasons really: First, people want foreign

實際上，有三大理由：一、人們拿

money for travel and tourism; second, foreign money is needed for trade, to buy foreign

外幣去外地旅遊觀光；二、外幣可用來交易國外商品或服務；

goods and services; third, foreign money is needed for investment purposes, be it financial

三、外幣可用來當作投資的標的，作為金融性投資

investment, like purchase of foreign-denominated financial assets, or real investment, like

如外國證券，或實質投資

building a new factory overseas. A change in any of these three components will alter

如在海外建廠。只要這三項因素有所改變，

the demand for foreign exchange.

外匯的需求面就會改變。

For example, a lot of recent Hollywood blockbuster movies have been filmed in New Zealand; what

例如：最近許多好來塢的賣座片都在紐西蘭拍攝，

if this creates a sudden surge in tourists going to New Zealand? These tourists will

這會不會對當地造成一股觀光熱潮？這些觀光客

need New Zealand dollars, creating an increase in demand for that currency. Similarly, if

需要紐西蘭幣(紐元)，這就會讓該幣的需求增加。同樣的，

US companies decide they’d like to build factories in New Zealand (real investment),

如果美國一間有名的企業打算在紐西蘭設廠(一種實質投資)，

or purchase NZ$-denominated financial assets (financial investment), the demand for the

或增加以紐元計價的證券投資(金融性投資)，紐元的

New Zealand dollar would increase.

需求會上升。

Now let's go back to the idea of the foreign exchange market, with the New Zealand dollar

現在，讓我們回到以紐元計價的

being the foreign exchange. Initially, there is a certain supply of New Zealand dollars,

外匯市場。一開始，會有一定數量的紐元供給和需求。

and a certain demand. The equilibrium price in this market is called the exchange rate.

該市場的平衡價格即為「匯率」。

OK; now let's throw the increase in demand for the New Zealand dollar into the picture.

現在，我們在圖裡增加當紐元需求增加時所畫出的需求線。

What happens to the value of the New Zealand dollar as more tourists travel there, or as

當有更多的觀光客湧進新紐西蘭，或更多的美國廠商想在該地投資時，

more US companies invest? As with any commodity, when the demand for the New Zealand dollar

紐元的價值發生了什麼改變？就像其他商品，當紐元的需求增強時，

increases, its value increases. We see the exchange rate, in terms of the US dollar per

其價值也會上升。我們看到，以美元/紐元計價的匯率，

New Zealand dollar, increase. This is called an appreciation of the New Zealand dollar.

升高了。這稱為紐元的「升值」。

When dealing with bilateral exchange rates like this one -- that is to say, the relative

當處理這種雙邊實質匯率，也就是，

value of two currencies – it is necessarily the case that is one currency becomes stronger,

兩種貨幣的相對價值，其中一種貨幣會比另一種還強勢，

or more valuable, relative to the other -- in this case, the New Zealand dollar is increasing

也就是其價值增加了。在這個例子哩，紐元相較於美元

in value relative to the US dollar -- the other currency is decreasing in value, or

變得比較強勢，也就是另外一種貨幣，價值下降了，也就是所謂的「貶值」。

depreciating. In this example, as the New Zealand dollar appreciates, the US dollar

在這個例子哩，當紐元升值時，美元相對而言

is getting relatively weaker, or depreciating.

就變得比較弱勢，也就是貶值了。

OK, so changes in demand for currency will affect the exchange rate. What about changes

好，所以改變貨幣需求會影響匯率。那改變貨幣供給呢？

in supply? Well, ultimately who is it that controls the supply of foreign currency? The

事實上，我們想問的是：究竟是什麼因素在影響外幣的供給？

foreign government. If the US wanted to drive the value of its own currency up, it would

答案是外國的政府。如果美元想要升值，

decrease the supply of dollars. If it wanted to drive value down, it would increase the

它只需要降低貨幣供給就可以了。如果美元想要貶值，它只需要

supply of dollars. Why would a country one manipulate its own currency value?

增加貨幣供給就可以了。為什麼一個國家的政府會想改變其貨幣價值？

Let me give you an example. Suppose you are a US furniture producer, and government protection

讓我給你一個例子：假設你是一個美國家具製造商，而政府

for the spotted owl means you can’t get the lumber that you need domestically. So

打算保護斑點鴞的棲息地，這表示你沒辦法在國內取得木材。

you call up a Canadian lumber mill, tell them you’d like to place an order, and they tell

所以你決定打給位在加拿大的製木場，告訴他你想訂購一些木材，

you that the lumber is going to cost CAN$50,000. I don’t know about you, but my bank account

而對方回應你說：費用是加幣50000元。我不知道你的情況，不過至少我的銀行帳戶裡

doesn't happen to have any Canadian dollars in it. This is where the exchange rate comes

是沒有加幣的。這時：匯率就變得重要起來了。

in. If I can figure out how much one Canadian dollar costs, then I can use that to calculate

如果我能算出一加幣等於多少美金的話，那我就可以算出

how much 50,000 Canadian dollars will cost. The price of one Canadian dollar, in terms

50000加幣值多少美金。一加幣等於多少美元，

of US dollars, is the exchange rate (dollars per Canadian dollar). I checked the dollar

就是匯率(美元/加幣)。我在x-rate.com查了一下

per Canadian dollar exchange rate for April 7, 2010 on x-rates.com, and found that CAN$1

2010年4/7加幣對美元的匯率，發現1加幣

was equivalent to US$.998.

相當於0.998美元。

Just as a side note, this nearly one-to-one parity between the two country’s currencies

順便提一下，其實這種兩國貨幣接近1:1平價的狀況

is highly unusual. More on that in a minute.

並不常見。情況很罕見。

So if one Canadian dollar costs 99.8 cents US currency, how much will CAN$50,000 cost?

所以如果1加幣相當於99.8美分的話，那50000加幣值美金多少錢？

In the end, it will cost you US$49,900 to purchase the Canadian lumber. Now let’s

最後，你會發現你需要花49900美元來向加國製木場購買木材。(譯注：影片中的圖畫打錯了，應該是49900美元才對)

take a little trip back in time, and figure out how much that same C$50,000 worth of lumber

現在，我們來稍微時光倒流一下，看看最近這20年內，加幣50000元

would've cost in April of each year for the previous 20 years. When would you most like

在每年4月時各值美金多少錢。在哪個時間點下

to have purchased that lumber? You can see by looking at the data, that when the foreign

你會最想去購買這批木材？在審視這些資料後，你會發現

currency is the cheapest, in this case 2001, at $.64 per Canadian dollar, the foreign imports

當外幣最便宜時(也就是外幣相對弱勢時)，在這個例子裡是2001年，1加幣等於0.64美元，

are the cheapest -- US$32,000. Even if the Canadian lumber mill sees the same CAN$50,000

從外國進口商品會最便宜-值32000美元。即使每年從加拿大進口木材都是50000加幣，

every year, the price to the US importer changes as the exchange rate changes. When the Canadian

但美國進口商實際付出的美金是隨匯率而變動的。當加幣

dollar depreciates, the lumber is cheaper, and US importers will buy more lumber. On

貶值時，(外國進口加國)木材就會變得比較便宜，而美國進口商就會想進口更多木材。

the flip side, as the Canadian dollar depreciates, the US dollar is getting stronger relative

另一方面，當加幣貶值時，美元對加幣就會變得比較強勢，

to the Canadian dollar, or it’s appreciating. While US consumers are enjoying a strong dollar

或可以說是美元升值。當美國的消費者靠著美元的強勢

and buying lots of Canadian goods, Canadians are seeing the US dollar, and therefore US

買進許多加國商品時，加拿大人會覺得美元，和

goods, as more expensive. Canadians import fewer US products if the Canadian currency

美國的商品，比較貴。加拿大在其貨幣比較弱勢時，會進口比較少的美國商品。

is weak. A weak Canadian dollar is good for Canada's trade balance, as Canada's exports

弱勢的加幣對加拿大的淨出口比較有優勢，因為

rise and imports fall. At the same time, the US trade balance gets worse -- we are importing

加拿大的出口增加，進口減少。而美國的貿易帳變得比較差，

more and exporting less.

進口更多而出口更少。

The effect of the currency value on the trade balance takes me back to the question: why

貨幣價值對淨出口的效果讓我們可以回答先前的問題：

would a country want to manipulate its own currency value? You now know the answer to

為什麼一個國家會想要操控該國的貨幣價值？現在你知道答案了。

this; if a country can keep its currency cheap, then it keeps its products cheap, and foreign

如果該國的貨幣比較便宜，則其商品也會比較便宜，

products expensive -- both of which are good for the balance of trade.

外國商品相對的就比較貴。這兩種效果都對淨出口有利。

The US has certainly been after China during the first decade of the 21st century; China

美國現在的貿易量在21世紀的第一個十年僅落後於中國；

keeps its currency value artificially low in order to keep favorable trade balance.

中國以人為的方式強制讓人民幣低於正常水準，以讓淨出口增加。

NEXT TIME: Comparative advantage and trade

下一節：比較利益的交易模式