The macroeconomy
A-Level Economics Topic 4 17:12 English narration · English + 中文 subtitles burned in
Chapters
Transcript
A city at night: every light is somebody working, building, selling.
夜晚的城市。 每一盏灯背后，都有人在工作、建造、买卖。
A shelf of food: every price tag changed this year.
还有一排食品货架，上面每一个价签今年都变过。
An economy is too big to see, so we measure it — and the numbers decide what a government does next.
经济体太大了，看不见，所以我们去测量它—— 而几个数字就决定了政府下一步怎么做。
How do you tell whether a whole economy is healthy?
那么，怎么判断整个经济体是否健康？
Three questions.
问三个问题。
Output: how much it produces, and is that growing.
产出：它生产了多少，是否在增长。
Jobs: who wants a job and cannot find one.
就业：谁想工作却找不到工作。
Prices: what money can buy now, next to last year.
价格：今年的钱和去年比，能买到什么。
That is this topic — and one diagram links all three.
这就是本专题——而且有一张图把这三者联系在一起。
First, measuring.
先说测量。
National income is the value of everything a country makes in a year.
国民收入，是一个国家一年里生产的全部价值。
Gross domestic product counts what is made inside the country; gross national income adds what its people earn abroad.
国内生产总值算的是在本国境内生产的东西； 国民总收入还要加上本国居民在国外挣到的收入。
Nominal uses today's prices; real strips price rises out.
名义值用当年价格；实际值把物价上涨扣掉。
And per capita means per person.
而人均，就是每人平均。
Drill the two labels carefully.
这两个标签要仔细分清。
Gross domestic product is everything made inside the borders.
国内生产总值是国界以内生产的全部。
Gross national income starts from that total, adds what residents earn abroad, and subtracts what foreigners earn inside the country.
国民总收入从那个总额出发，加上本国居民在国外挣的， 再减去外国人在本国境内挣的。
When you compare years, always use real values — nominal can jump only because prices rose.
比较不同年份时，永远用实际值——名义值可能只因物价上涨而跳升。
Total output can also mislead: a bigger country usually has a bigger total, so per person is the fairer living-standard measure.
总产出也会误导：大国通常总额更大，所以人均才是更公平的生活水平尺度。
Why measure national income at all?
为什么要测量国民收入？
Governments use it to judge the standard of living and to compare one country with another.
政府用它判断生活水平，并拿一国与另一国比较。
Growth rates show whether living standards are rising.
增长率显示生活水平是否在提高。
Aid and tax policy often track these numbers.
援助和税收政策也常跟着这些数字走。
But a high average income is only a starting point for that judgement — the next figure shows what the average hides.
但较高的平均收入只是判断的起点——下一张图会说明平均值掩盖了什么。
Output per person is how we compare living standards.
我们用人均产出来比较生活水平。
But it hides a lot.
但它掩盖了很多东西。
It ignores the distribution of income, so a comfortable average can hide deep inequality.
它没有说收入落到谁手里，所以看着不错的平均值下面，可能是严重的不平等。
It leaves out unpaid work and the informal economy, and counts pollution as nothing.
它漏掉了没有报酬的劳动和非正规经济，也完全不算污染。
A higher figure usually means a better life — not always.
数字更高通常意味着生活更好，但并不总是如此。
Three more gaps the exam likes.
考试还爱考另外三个缺口。
Unpaid housework is real work, but national income ignores it.
没有报酬的家务劳动是真正的工作，但国民收入不算它。
The informal economy — hidden, untaxed activity — is left out too.
非正规经济——隐藏的、不缴税的活动——也被漏掉。
And the figures say nothing about leisure time or health: a country can raise output by working longer hours while people feel worse.
这些数字也不谈闲暇时间和健康：一国可以靠加长工时提高产出，人们却感觉更糟。
So treat gross domestic product per person as a useful guide, never as the whole story of welfare.
所以把人均国内生产总值当作有用的指引，绝不要当成福利的全部故事。
This is the circular flow of income — the picture behind every macro number.
这就是每一个宏观数字背后的图。
Households own the workers and the land; firms use them and pay wages, rent and profit.
家庭拥有劳动力和土地； 企业使用它们，付出工资、租金和利润。
Households spend that income back, so money goes round.
家庭再把收入花回商品上，钱就转了一圈。
It leaks out as saving, taxes and imports, and returns as investment, government spending and exports.
钱会漏出去，变成储蓄、税收和进口；又以投资、政府支出和出口回来。
When the two match, the flow is in equilibrium; when injections are bigger, the economy grows.
当两者相等，循环流就处于均衡；当注入更多时，经济就增长。
Pause on the labels.
在标签上停一下。
Households supply factors of production — labour, land, capital and enterprise.
家庭提供生产要素——劳动、土地、资本和企业家才能。
Firms pay them wages, rent, interest and profit.
企业付给他们工资、租金、利息和利润。
That income comes back as spending on goods and services.
这些收入再以商品和服务的支出流回。
Money also leaves as three leakages: saving, taxation and imports.
钱也会以三种漏出离开：储蓄、税收和进口。
Three injections put money back in: investment, government spending and exports.
三种注入把钱送回来：投资、政府支出和出口。
Learn those six words as two matching lists.
把这六个词当成两组对应的名单来记。
A closed economy has no trade with other countries, so no exports and no imports in the flow.
封闭经济不与别国贸易，所以循环流里没有出口和进口。
An open economy trades, and those two channels matter.
开放经济会贸易，这两条通道就很重要。
Equilibrium means total injections equal total leakages.
均衡意味着总注入等于总漏出。
If injections are greater, national income rises and the economy grows.
若注入更大，国民收入上升，经济就增长。
If leakages are greater — more saving, tax or imports than investment, government spending and exports — the flow shrinks and output falls.
若漏出更大——储蓄、税收或进口多于投资、政府支出和出口—— 循环流就收缩，产出下降。
Exam questions love that comparison.
考题很爱这种对比。
Now the model the exam is built on.
现在来看考试所依据的模型。
Aggregate demand is total spending on a country's output at each price level, and it has four parts.
总需求，是在每一个价格水平上， 对一个国家产出的总支出，它有四个部分。
Consumption, by households, is by far the biggest.
消费来自家庭，也是最大的一块。
Investment is firms buying capital.
投资是企业购买资本品。
Then government spending.
再加上政府支出。
And net exports: exports minus imports, which can be negative.
最后是净出口，也就是出口减进口，可以是负数。
Change one part, and the whole curve moves.
改变其中一部分，整条曲线就会移动。
Say the equation in words: aggregate demand equals consumption plus investment plus government spending plus net exports.
用话把等式说出来：总需求等于消费加投资加政府支出再加净出口。
A tax cut leaves households with more to spend, so consumption rises and demand shifts right.
减税让家庭能花的钱更多，于是消费上升，需求曲线向右移。
Cheaper loans raise investment.
贷款更便宜会提高投资。
Extra public projects raise government spending.
更多公共项目会提高政府支出。
Stronger foreign demand or a weaker currency can lift net exports.
更强的外国需求或更弱的本币，可能抬高净出口。
Name the part that changed — then shift the whole curve.
先指出变了的部分——再移动整条曲线。
Now demand and supply for the whole economy.
现在看整个经济的需求和供给。
Demand slopes down: a lower price level means spending buys more, so more output is demanded.
需求曲线向下倾斜：价格水平更低， 支出能买到更多，所以被需求的实际产出更多。
Short run supply slopes up: higher prices make producing more profitable.
短期供给曲线向上倾斜，因为价格更高时生产更有利可图。
Long run supply is vertical — full capacity, moved only by more or better factors.
长期供给曲线是垂直的——那是全部生产能力， 只有生产要素更多或更好才能让它移动。
Where they cross, read off the price level and real output.
曲线相交的地方，就读出价格水平和实际产出。
Macroeconomic equilibrium is where aggregate demand crosses aggregate supply.
宏观经济均衡，就是总需求与总供给相交的地方。
From that point, read the price level on the vertical axis and real output on the horizontal axis.
从那个交点，在纵轴读价格水平，在横轴读实际产出。
In the short run the crossing is with short run supply.
短期内，交点落在短期供给上。
The vertical long run line marks full capacity — potential output.
垂直的长期线标出全部产能——潜在产出。
If the short run crossing sits left of that line, spare capacity remains.
若短期交点在那条线左边，说明还有闲置产能。
A shift in either curve moves both price and output.
任一条曲线移动，价格和产出都会一起变。
Now watch a shift.
现在看曲线移动。
Households spend more, so aggregate demand moves right.
家庭花得更多，于是总需求向右移动。
The crossing point slides up the supply curve: output rises, and the price level rises with it.
交点沿着供给曲线向上滑：实际产出上升，价格水平也跟着上升。
That move answers a lot of exam questions.
这一个动作，就能回答大量考题。
Name the part of demand that changed, shift that curve, read off the new output and price level.
指出总需求中哪一部分变了，把那条曲线移动，再读出新的产出和价格水平。
Supply moves too.
供给也会移动。
Short run supply shifts when firms' costs change — higher wages, dearer raw materials, or taxes on production push the curve left, so less is supplied at every price level.
短期供给在企业成本变化时移动—— 更高的工资、更贵的原材料，或生产税，会把曲线推向左边， 于是在每一个价格水平上供给都更少。
Lower costs push it right.
成本下降则推向右边。
Long run supply only shifts when the quantity or quality of factors changes: more workers, better skills, new capital, or new technology.
长期供给只有在生产要素的数量或质量变化时才移动： 更多工人、更好技能、新资本或新技术。
That is a rise in productive capacity, not just a cost shock.
那是生产能力的提高，不只是一次成本冲击。
Economic growth is a rise in real output over time, and it splits in two.
经济增长是实际产出随时间的上升，它可以分成两种。
Actual growth really happens — using more of the capacity you already have.
实际增长是真正发生的上升——用上了本来就有的更多产能。
Potential growth raises that capacity, shown by long run supply shifting outward.
潜在增长是产能本身的提高，表现为长期供给曲线向外移动。
It comes from a bigger, better trained workforce, more investment, new technology and higher productivity.
它来自更多、受过更好训练的劳动力，更多投资，新技术，以及更高的生产率。
Actual growth is a movement towards full capacity — using spare plant and idle workers — or a rise in real output that you can measure year to year.
实际增长是朝向全部产能的移动——用上闲置厂房和闲置工人—— 或者是你能逐年测到的实际产出上升。
Potential growth is different: the whole capacity frontier moves out, so long run supply shifts right.
潜在增长不同：整个产能边界外移，所以长期供给向右移。
Higher productivity — more output per worker — is a classic cause.
更高的生产率——每个工人产出更多——是经典原因。
Investment in machines and skills builds potential; a short boom alone does not.
对机器和技能的投资建立潜在能力；单靠一次短繁荣不够。
Real output does not grow in a straight line.
实际产出不会沿直线增长。
It swings above and below its long run trend: the business cycle.
它围绕长期趋势上下摆动，这种摆动就是经济周期。
Output climbs through a boom — also called an expansion — to the peak.
产出在繁荣中上升——也叫扩张——一直到顶峰。
Then a recession takes it down to the slump, also called the trough.
然后衰退把它带到最低点：萧条，也叫谷底。
Recovery follows, and the pattern repeats.
接着是复苏，整个过程重复。
Learn both sets of names.
两套名称都要记住。
The same pattern is also called the trade cycle.
同一模式也叫贸易周期。
Say the four phases in order: boom, recession, slump, recovery.
按顺序说出四个阶段：繁荣、衰退、萧条、复苏。
In a boom, real output rises fast and unemployment tends to fall.
繁荣时，实际产出快速上升，失业率往往下降。
In a recession, output falls for a period.
衰退时，产出在一段时期内下降。
The slump is the low point.
萧条是最低点。
Recovery is the climb back towards trend.
复苏是爬回趋势的过程。
The upward trend line is long-run growth; the wave around it is the cycle.
向上的趋势线是长期增长；绕着它的波是周期。
Growth is not free, and the exam wants both sides.
增长不是免费的，考试要求你写出两个方面。
The benefits: higher incomes and living standards, more jobs, less poverty, more tax for schools and hospitals.
好处：收入和生活水平提高、就业增加、贫困减少， 政府也有更多税收用于学校和医院。
The costs: if demand grows faster than supply, prices rise; production uses resources and pollutes; and the rich-poor gap can widen.
代价：如果需求增长快过供给，物价就会上涨；生产消耗资源，还造成污染； 而且贫富差距可能扩大。
In a long answer, always balance the two columns.
写长答案时，永远要平衡两栏。
Higher growth can cut poverty and fund public services — but only if the gains are shared and if demand does not outrun supply.
更高的增长可以减少贫困、资助公共服务—— 但前提是收益被分享，而且需求没有跑在供给前面。
Inflation from too-fast demand is a common cost.
需求过快带来的通货膨胀是常见代价。
Pollution and resource use hurt future living standards.
污染和资源消耗会损害未来的生活水平。
Inequality can rise if the new income lands mainly with owners of capital.
若新收入主要落在资本所有者手里，不平等可能上升。
State the benefit, then the cost, then a short judgement.
先写好处，再写代价，最后给一句简短判断。
Unemployment means people able to work, willing to work and looking for work, who cannot find a job.
失业，指的是有能力工作、愿意工作、也在找工作，却找不到工作的人。
Four types.
共有四种。
Frictional is short — between one job and the next.
摩擦性失业是短期的——正处在两份工作之间。
Structural is deeper — an industry declines and your skills no longer match.
结构性失业更深——一个行业衰落，你的技能对不上了。
Cyclical comes from low demand in a recession, usually the largest.
周期性失业来自衰退时的低需求，通常是最大的一种。
Seasonal work exists only at certain times of year.
季节性工作只在一年中的某些时候才有。
Link each type to a fix the exam expects.
把每一种类型和考试期望的对策连起来。
Frictional needs better job information and help matching people to vacancies.
摩擦性需要更好的职位信息， 以及帮人匹配空缺。
Structural needs retraining and sometimes help to move to where jobs are.
结构性需要再培训，有时还要帮人迁到有工作的地方。
Cyclical needs higher aggregate demand — so government spending, tax cuts or looser money can help in a recession.
周期性需要更高的总需求——所以衰退时政府支出、减税或更宽松的货币可能有用。
Seasonal jobs in farming or tourism come and go with the calendar; that is not the same as a skills mismatch.
农业或旅游业的季节性工作随日历来去；那和技能错配不是一回事。
There are two official counts.
官方有两种统计口径。
The claimant count records only benefit claimants — cheap and quick, but it misses anyone looking for work who does not claim.
申领救济人数只统计领取救济金的人：便宜又快， 但会漏掉在找工作却不申领的人。
The labour force survey asks a large sample whether they work or are looking.
劳动力调查向一个大样本询问他们是否在工作或在找工作。
Dearer, but it follows an international standard, so it compares countries better.
它更贵，但遵循国际标准，所以更适合比较不同国家。
Either way, unemployment wastes output and costs the government.
不论用哪一种，失业都浪费产出，也让政府付出代价。
The labour force is everyone working or actively looking for work.
劳动力是所有在工作或在积极找工作的人。
People who have stopped looking — full-time students, early retirees, carers — sit outside it.
已经停止寻找的人——全日制学生、提前退休者、照护者——在劳动力之外。
The unemployment rate is the unemployed as a share of the labour force, not of the whole population.
失业率是失业者占劳动力的比例，不是占全体人口的比例。
That is why the survey definition matters: it asks about job search, not only about benefit claims.
所以调查定义很重要：它问的是求职，不只是救济申领。
Unemployment is costly in four ways.
失业从四个方面带来代价。
First, it wastes real output — the economy produces inside its production possibility frontier because idle workers make nothing.
第一，它浪费实际产出—— 经济在生产可能性边界之内运转，因为闲置工人什么也不生产。
Second, household incomes fall, so spending drops.
第二，家庭收入下降，支出随之减少。
Third, the government pays more in benefits and collects less tax.
第三，政府多付救济、少收税收。
Fourth, long spells harm families and can raise crime and ill health.
第四，长期失业伤害家庭，还可能抬高犯罪和健康问题。
That is why macro policy treats high unemployment as an emergency, not a statistic.
所以宏观政策把高失业当成紧急情况，而不是一个统计数字。
Now prices.
现在看价格。
Inflation is a sustained rise in the general price level, so money buys less — purchasing power falls.
通货膨胀是一般价格水平的持续上升，钱能买的东西变少了—— 购买力下降。
Deflation is the opposite: a sustained fall.
通货紧缩正好相反：价格持续下降。
Disinflation is the one students get wrong — prices still rise, just more slowly.
而反通货膨胀是学生最容易搞错的——价格仍在上升，只是涨得更慢。
We measure it by pricing a basket of what a household buys, weighted by the amount spent.
我们给一篮家庭购买的商品定价，按支出金额加权。
That is the consumer price index.
这就是消费者价格指数。
Build the consumer price index from a typical household basket.
用典型家庭的一篮子商品构建消费者价格指数。
Bread, rent, fuel, phones — each good gets a weight for how much is spent on it.
面包、房租、燃料、手机——每样商品按支出多少加权。
Housing weighs more than a rare treat.
住房的权重大过偶尔的零食。
Track the basket cost from year to year.
逐年追踪这篮子的费用。
The inflation rate is the change in the index, divided by the starting index, times one hundred percent.
通货膨胀率是指数的变化量，除以起始指数，再乘以百分之一百。
Always divide by last year's index, not by a fixed base you happen to remember.
永远除以上一年的指数，不要除以你碰巧记住的某个固定基准。
Now use it.
现在来用一用。
A price index is one hundred, then one hundred and four, then one hundred and seven.
一个价格指数是一百，然后是一百零四，再是一百零七。
Find the inflation rate in each year.
求每一年的通货膨胀率。
Year one first.
先看第一年。
Take the change in the index, four, divide by the starting index, one hundred, then multiply by one hundred.
取指数的变化量，四， 除以起始的指数，一百，再乘以一百。 得到百分之四。
That gives four percent.
再看第二年。
Year two. The change is three, but this time divide by one hundred and four.
变化量是三，但这一次要除以一百零四。
That gives two point nine percent.
得到百分之二点九。
Here is the trap: divide by the previous year's index, never the base year.
这里有个陷阱：永远除以上一年的指数，绝不是基准年。
And read it carefully — inflation fell, but prices still went up.
而且要仔细读结果。 通货膨胀率下降了，但价格仍然在上涨。
That is disinflation, not deflation.
这叫反通货膨胀，不是通货紧缩。
Second worked example.
第二个例题。
A worker's weekly pay rises from five hundred pounds to five hundred and twenty — that is a four percent rise.
一名工人的周薪从五百英镑涨到五百二十——涨了百分之四。
In the same year prices also rise four percent.
同一年物价也涨了百分之四。
What happens to the real wage?
实际工资会怎样？
Money pay is up four percent, but prices are up four percent too, so the real wage is unchanged.
货币工资涨了百分之四，但物价也涨了百分之四，所以实际工资没有变。
Living standards rise only if the pay rise beats inflation.
只有工资涨幅跑赢通货膨胀，生活水平才会提高。
Where does inflation come from?
通货膨胀从哪里来？
Two routes.
有两条路径。
Demand pull: demand rises faster than supply can follow, so too much spending chases too few goods — demand shifts right, and the price level goes up.
需求拉动型：需求上升得比供给跟得上的速度更快，太多的钱去追太少的商品—— 需求曲线向右移动，价格水平上升。
Cost push: wages, raw materials or imported energy get dearer, so firms supply less at every price — short run supply shifts left.
成本推动型：工资、原材料或进口能源变贵， 所以企业在每一个价格上都供给得更少——短期供给曲线向左移动。
Same result, opposite cause, different curve.
结果相同，原因相反，移动的曲线也不同。
Draw both diagrams in an exam.
考试里两张图都要会画。
Demand-pull: shift aggregate demand right; the price level rises and real output may rise too.
需求拉动：把总需求向右移； 价格水平上升，实际产出也可能上升。
Cost-push: shift short run supply left; the price level rises while real output falls — stagflation territory.
成本推动：把短期供给向左移；价格水平上升，实际产出却下降——滞胀地带。
The classic phrase for demand-pull is too much money chasing too few goods.
需求拉动的经典说法是：太多的钱去追太少的商品。
For cost-push, name the cost: wages, oil, or imported materials.
成本推动则要指出成本：工资、石油，或进口原材料。
Another way to remember the split.
记住这种划分的另一方法。
Demand-pull starts with demand rising faster than supply can keep up, and prices climb.
需求拉动从需求上升快过供给跟进开始，价格上扬。
Cost-push starts with firms' costs — wages or materials — and firms pass those costs into higher prices.
成本推动从企业成本——工资或材料——开始，企业把成本转成更高价格。
Both end with a higher price level, so you cannot tell them apart from the price number alone.
两者都以更高的价格水平收尾，所以单看价格数字分不清。
You need the story and the diagram.
你需要故事，也需要图。
Inflation eats the value of money.
通货膨胀吃掉了钱的价值。
Suppose your pay rises four percent while prices rise four percent too — then your real wage has not changed at all.
假设你的工资涨了百分之四，而物价也涨了百分之四——那么你的实际工资完全没有变。
A pay rise only helps if it beats inflation.
涨工资只有跑赢通货膨胀才有意义。
Savers and people on fixed incomes lose: the money they hold buys less each year.
储蓄者和靠固定收入生活的人吃亏：他们手里的钱每年能买的东西更少。
Borrowers gain, repaying in cheaper money.
借款人获利，因为他们用更便宜的钱还债。
Exports become dearer abroad and sell less.
出口在国外变贵，所以卖得更少。
And falling prices are no gift — in deflation people wait for cheaper goods, and jobs go.
物价下跌也不是好事——在通货紧缩中，人们等着东西更便宜，工作岗位就没了。
Inflation also creates uncertainty: firms delay investment when they cannot predict future costs and prices.
通货膨胀还会制造不确定性：企业无法预测未来成本和价格时，就会推迟投资。
Deflation sounds helpful but can spiral.
通货紧缩听起来有帮助，却可能螺旋恶化。
People wait for still-lower prices, so aggregate demand falls.
人们等着价格再降，于是总需求下降。
Firms cut output and jobs.
企业削减产出和岗位。
Incomes fall, demand falls again.
收入下降，需求再降。
That is why policy makers fear a sustained fall in the price level, not only a rise that runs too hot.
所以决策者害怕价格水平的持续下跌， 不只是过热的上涨。
Three marks students throw away.
三个学生常丢的分。
First, compare real values, never nominal — and for inflation, divide by the previous year's index.
第一，比较实际值，绝不用名义值—— 而且算通货膨胀时，要除以上一年的指数。
Second, know the four parts of aggregate demand and what changes each: a tax cut moves demand, a wage rise moves supply.
第二，记住总需求的四个组成部分，以及什么会改变每一部分： 减税让需求移动，工资上涨让供给移动。
Third, say which curve moves and which way — demand pull pushes demand right, cost push pushes supply left.
第三，说清楚哪条曲线移动、往哪个方向——需求拉动把需求推向右边， 成本推动把供给推向左边。
Four pillars for the exam.
考试的四根支柱。
National income: use real, per person figures, and know what they miss.
国民收入：用实际的、人均的数字，并知道它们漏了什么。
Aggregate demand and supply: the four parts of demand, short run and long run supply, and equilibrium price and output.
总需求与总供给：需求的四个部分、短期与长期供给，以及均衡的价格和产出。
Unemployment: four types, two measures, and the real costs.
失业：四种类型、两种度量，以及真实代价。
Inflation: consumer price index, demand-pull versus cost-push, and why deflation is not a free gift.
通货膨胀：消费者价格指数、需求拉动对成本推动，以及为何通货紧缩不是白送的礼物。
If you can draw and label those ideas, most questions open up.
若你能画出并标出这些想法，多数题目就打开了。