Open Economy—International Trade and Finance
AP Macroeconomics Topic 6 8:01 English narration · English + 中文 subtitles burned in
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Transcript
Check the label on almost anything you own. Made somewhere else.
看看你身边几乎任何东西上的标签，都是别处生产的。
It crossed an ocean in a steel box like these, and somebody paid for it in a different money.
它装在这样的钢制集装箱里漂洋过海， 而付款用的是另一种货币。
So: how do we count what crosses a border?
那么：我们如何记录跨境的一切？
And who sets the price of one money in another?
一种货币相对另一种货币的价格又由谁决定？
Here is the road ahead.
先看看我们要走的路。
The balance of payments, and the two accounts every country keeps.
国际收支，以及每个国家都记的两个账户。
Exchange rates, and what a rise or a fall really means.
汇率， 以及升值或贬值到底意味着什么。
The foreign exchange market, and what moves it.
外汇市场，以及是什么让它变动。
Net exports.
净出口。
And last, real interest rates and capital flows.
最后是实际利率与资本流动。
Every transaction that crosses a border goes into one system: the balance of payments.
每一笔跨境交易都记入同一个体系：国际收支。
It has two accounts.
它分为两个账户。
The current account is about trade — goods, services, and the income that travels with them.
经常账户记录贸易—— 物品、服务，以及随之而来的收入。
The financial account, which the exam calls the capital and financial account, is about assets: bonds, shares, whole factories.
金融账户，考试里称为资本与金融账户， 记录资产：债券、股票，甚至整座工厂。
Look closer at the current account.
我们细看经常账户。
It has four parts.
它有四个部分。
Trade in goods — physical exports and imports, the containers on that ship.
物品贸易——有形的出口与进口，也就是船上的集装箱。
Trade in services — tourism, banking, insurance.
服务贸易——旅游、银行、保险。
Primary income — wages, profit and interest earned abroad.
初次收入——在国外获得的工资、利润和利息。
And secondary income — transfers and aid.
以及二次收入——转移与援助。
Net exports live in the first two boxes.
净出口就在前两个方框里。
Now the rule that ties them together.
现在来看把两者联系起来的规则。
The balance of payments records every transaction, and the two accounts are mirror images.
国际收支记录每一笔交易，而这两个账户互为镜像。
Buy more goods than you sell, and your current account is in deficit.
买的物品多于卖的，你的经常账户就是逆差。
But that money comes back, because foreigners use it to buy your assets — so the financial account is in surplus.
但那些钱会回来， 因为外国人用它来购买你的资产——于是金融账户就是顺差。
Add the two together and you always get zero.
把两者相加，永远得到零。
That offset is what the exam tests.
考试考的正是这种抵消。
An exchange rate is just a price: the price of one currency in another.
汇率其实就是一个价格：一种货币用另一种货币表示的价格。
Most are floating exchange rates, so supply and demand move them all day.
多数货币是浮动的， 供求整天都在推动它。
Worth more, and we say it appreciates; worth less, and it depreciates.
变得更值钱，我们说它升值；变得不值钱，就是贬值。
On this slide, one dollar goes from seven yuan to eight.
这张幻灯片上，一美元从七元人民币变成八元。
The dollar buys more yuan, so the dollar appreciated.
美元能换到更多人民币，所以美元升值了。
Here is the trap.
这里有个陷阱。
Start with one dollar worth nought point nine euros.
先看一美元值零点九欧元。
Now the dollar rises, and one dollar buys a full euro.
现在美元上涨，一美元能换一整欧元。
One dollar now buys more euros, so the dollar appreciated.
一美元现在能换到更多欧元，所以美元升值了。
But turn it around.
但反过来看。
One euro used to buy one dollar and eleven cents; now it buys only one.
一欧元原本能换一点一一美元， 现在只能换一美元。
The euro buys fewer dollars, so the euro depreciated.
欧元换到的美元变少了，所以欧元贬值了。
One event, two names — so always check which currency the question is about.
同一件事，两种说法—— 所以一定要看清题目问的是哪种货币。
Answer for the wrong one, and the mark is gone.
答错了货币，分就没了。
So where is that price set?
那么这个价格在哪里决定？
In the foreign exchange market.
在外汇市场。
Quantity of the currency runs along the bottom, the exchange rate up the side.
横轴是这种货币的数量，纵轴是汇率。
Demand slopes down — foreigners who want our goods, our services or our assets.
需求向下倾斜——来自想买我们物品、服务或资产的外国人。
Supply slopes up — our own residents buying foreign things.
供给向上倾斜—— 来自购买外国东西的本国居民。
Where they cross, the rate is set.
两条线相交的地方，汇率就定下来了。
Here is the same market, drawn for the pound.
这是同一个市场，画的是英镑。
The first crossing gives the starting rate.
第一个交点给出起始汇率。
Now something raises demand for pounds — more people want British goods, or British bonds.
现在有什么推高了对英镑的需求—— 更多人想要英国物品，或英国债券。
Demand shifts right, to the dashed line.
需求右移到虚线的位置。
The new crossing sits higher, so each pound buys more foreign money.
新的交点更高， 所以每一英镑能换到更多外币。
That is an appreciation.
这就是升值。
What actually shifts those curves?
到底是什么让这些曲线移动？
Four things, and the exam names them as relative.
四样东西，而且考试都用“相对”来称呼它们。
Relative interest rates: raise yours at home and financial capital flows in — inflows — so demand for your currency rises and it appreciates; a lower rate causes outflows and depreciation.
相对利率：本国提高利率，金融资本就流入，对你货币的需求上升，货币升值； 利率更低则资本流出，货币贬值。
Relative price levels, or inflation: prices rising faster than everyone else's make your goods dear, so demand falls and your currency depreciates.
相对物价水平，也就是通货膨胀：物价涨得比别人快，你的物品显得贵， 需求下降，货币贬值。
Relative incomes: a richer country buys more imports, supplies more of its own money, and depreciates too.
相对收入：更富裕的国家买更多进口品，供给出更多本国货币，同样贬值。
And tastes — what buyers happen to want, and what they expect the currency to be worth later.
还有偏好——买家恰好想要什么，以及他们预期这种货币以后值多少。
Now the effect on trade, in one picture.
现在用一张图看它对贸易的影响。
On the left, appreciation: the currency is worth more, so our exports look dearer abroad and imports cheaper at home — exports fall, imports rise.
左边是升值：货币更值钱， 所以出口在外国人眼里更贵，进口在我们眼里更便宜——出口下降，进口上升。
On the right, depreciation, and every arrow reverses: exports rise, imports fall.
右边是贬值，每个箭头都反过来：出口上升，进口下降。
Learn this pair as one block.
把这一对当成一整块来记。
Put those together and you have net exports: exports minus imports.
把这些合起来，就得到净出口：出口减去进口。
A weaker currency raises net exports; a stronger currency lowers them.
货币走弱，净出口上升；货币走强， 净出口下降。
And net exports are one of the four parts of aggregate demand.
而净出口正是总需求的四个组成部分之一。
Look at the number here. A machine costs a European buyer nine hundred euros; after the dollar appreciates, a thousand.
看这里的数字： 一台机器让欧洲买家花九百欧元；美元升值后，要花一千欧元。
Now changes in policies and economic conditions.
再看政策和经济状况的变化。
A currency move reaches output.
汇率的变动会一路传到产出。
Let the currency depreciate: exports rise, imports fall, net exports rise, and aggregate demand shifts right — the same effect as an expansionary policy.
假设货币贬值：出口上升，进口下降，净出口上升，总需求右移—— 效果和扩张性政策是一样的。
Here is that shift.
这就是那次右移。
Equilibrium slides up the short-run supply curve, so real output rises and the price level rises with it.
均衡沿着短期供给曲线上滑，实际产出上升， 物价水平也随之上升。
An appreciation does the opposite.
升值则相反。
Now a real exam question.
现在来做一道真正的考题。
One euro equals one hundred yen.
一欧元等于一百日元。
An Italian coat costs one hundred and twenty euros.
一件意大利大衣价值一百二十欧元。
What is its price in yen?
它用日元标价是多少？
First, look at the rate.
首先看汇率。
One euro is worth a hundred yen, so euros into yen you multiply.
一欧元值一百日元，所以欧元换日元要用乘法。
Now multiply the price by the rate: one hundred and twenty, times one hundred.
现在把价格乘以汇率：一百二十乘以一百。
The answer is twelve thousand yen.
答案是一万二千日元。
And check it makes sense — one euro buys many yen, so the yen number must be bigger.
再检查是否合理—— 一欧元能换很多日元，所以日元的数字必须更大。
Same paper, next part.
同一份卷子的下一小问。
Real interest rates rise in Japan.
日本的实际利率上升。
Start by drawing the foreign exchange market for the yen — the currency the question names.
先画出日元的外汇市场—— 日元正是题目点名的货币。
Money chases the better return, so financial capital flows into Japan.
资金追逐更高的回报，于是金融资本流入日本。
To buy Japanese assets, foreigners must first buy yen, so demand for the yen rises and the curve shifts right.
要买日本资产，外国人必须先买日元，所以对日元的需求上升，曲线右移。
The new crossing is higher: the yen appreciates.
新的交点更高：日元升值。
A weaker euro follows, so Italy's exports to Japan rise.
欧元随之走弱，于是意大利对日本的出口上升。
One rate change moved money, then trade.
一次利率变动，先带动资金，再带动贸易。
Let's give that chain a name.
我们给这条链条起个名字。
Money chases the best real return.
资金追逐最高的实际回报。
If one country's real interest rate rises above the world rate, capital flows in: foreigners buy its assets, and to do that they must buy its currency, so the currency appreciates.
如果一个国家的实际利率高于世界利率， 资本就会流入：外国人购买它的资产，而要这样做就得先买它的货币，于是货币升值。
A stronger currency makes exports dearer, and the current account moves toward deficit.
更强的货币让出口变贵，经常账户走向逆差。
One last link, and it is the capstone of the course.
最后一个联系，也是整门课的收官技能。
A government running a budget deficit has to borrow, and borrowing is demand for loanable funds.
政府出现预算赤字就必须借钱， 而借钱就是对可贷资金的需求。
Demand shifts right and the real interest rate is bid up — the graph in front of you.
需求右移，实际利率被抬高——就是你眼前这张图。
A higher real rate pulls in foreign capital, the currency appreciates, and net exports fall.
更高的实际利率吸引外国资本流入，货币升值，净出口下降。
Economists call this the twin deficits.
经济学家称之为双赤字。
Three places students lose marks.
三个学生常失分的地方。
First, always graph the currency the question named — its price on the vertical axis, and you shift its own curve.
第一，永远画题目点名的那种货币—— 它的价格放在纵轴，而且移动的是它自己的曲线。
Drawing the other country's market is the commonest error here.
画成另一个国家的市场， 是这里最常见的错误。
Second, one rises means the other falls, so a stronger currency makes exports dearer and imports cheaper.
第二，一种货币上升就意味着另一种下降， 所以货币走强会让出口更贵、进口更便宜。
Third, the two accounts add to zero: a current-account deficit is matched by a financial-account surplus.
第三，两个账户之和为零： 经常账户逆差由金融账户顺差抵消。
Get those right, and Unit Six is yours.
把这些做对，第六单元就是你的了。