印度赶超中国？先渡两个劫再说吧

Dracula

关于印度的具体情况我不了解，不作评论。但是你关于美国大萧条的那段都是不正确的。首先你怎么可能会相信那时的意大利比美国工业化程度高呢？第二，如果你看过The Grapes of Wrath（愤怒的葡萄，小说和电影都是经典）的话，就不会说出大萧条对美国农民没有冲击这种话的。罗斯福新政很重要的一个方面就是针对农业的AAA。第三，美国当时也是有极右法西斯主义的势头的，最著名的是Father Couglin 和Huey Long，对罗斯福1936年连任造成了不少威胁，罗斯福新政最重要，最持久的成就Social Security（养老金、失业保险）的建立，在一定程度上可以说是对他们政策的窃取。

另外稳定金融尤其是银行系统是中央银行最重要的职能之一，在现代经济学家中是共识。象2008年美国的TARP，对美国银行系统的救助，在经济学家中有广泛的支持。我对印度的具体情况不了解，但是如果那里发生银行挤兑危机的话，我相信不论是中央银行还是政府还是都会很快做出反应应对的。

Dracula

五月 发表于 2017-9-6 11:30
我对美国大萧条的观点来自于一些介绍美国金融史的书。这些书偏重于讲述华尔街以及美国政府，关于三十年 ...

1929年的时候，美国的人均GDP工业化程度生产率等指标比德国都是高过不少的，更不要说意大利了。那时德国意大利城市人口的比例是多少我刚才没有查到，但美国是56.1%，多数的美国人口其实是住在城市。另外大萧条时的美国农民是很惨的，你有时间的话可以看一下The Grapes of Wrath，小说得了普利策奖，今天被公认是美国文学的名著。是美国很多高中语文课的必读书之一，电影也是那年的奥斯卡奖的得主，现在也被认为是经典，AFI评选的美国历史上最伟大的100部电影里排名排在第23，也是我看过的最伟大最感人的电影之一。

Dracula

五月 发表于 2017-9-6 12:41
去看了一下维基。迄今为止美国历史上有47次recession衰退、萧条或者经济危机。

也许我读书不仔细，当时 ...

把recession 翻译成经济崩溃不适合。NBER的定义是连续两个季度GDP降低，比如2001年美国网络泡沫破裂后有短暂的recession，没人会说那个时候美国经济崩溃了。而是恰恰相反90年代后期美国经济特别繁荣，2001年的时候只是算是一个短暂调整。

2战以前尤其是20世纪以前的经济数据的质量要低很多，因此你说的那个表上列的大多数经济衰退到底是不是衰退，是不是符合现代的NBER的定义其实并不是那么确定。就是是衰退，老百姓也不一定就会受很多苦，大萧条在美国经济史上是唯一就那么一次。尤其是二战后的情况，Robert Lucas有过一篇很有名的论文，他做过一个简单计算，如果抹平business cycle，看看老百姓的效用能提高多少，结论是至少就二战后的数据来看是微乎其微，相当于比GDP的千分之一稍多一点。

另外经常项目（也就是贸易）下的顺差，自动等于资本项目下的逆差，这是会计上的恒等式，永远是对的，和经济理论无关。解释了资本项目下的顺逆差也就自动解释了经常项目下的逆顺差，这是一枚硬币的两面，反之亦然。因此从贸易角度还是资本流动的角度来解释贸易顺逆差都能说的通，很多时候我觉得从资本流动角度解释更有道理。比如对日本多年贸易顺差的一个解释可以是日本外贸企业的强大，但我觉得更有道理的一个解释是日本非常低的出生率导致其未来人口老龄化非常严重。一个人要准备年老的话就需要多储蓄。从国际金融的角度讲，就是要多持有国外的金融资产，也就是说资本输出大于资本流入，资本项目下是逆差，那么也就意味着经常项目下必须是顺差。类似的，对中国贸易顺差的一个解释是在执行计划生育多年之后，fertility rate也是低于replacement level很多，未来加入老龄社会的速度也会很快。加上中国的社会保障相对来说很落后，中国人的储蓄率高也不是那么特别。而这自然也就意味着中国需要增加持有国外资产，这也就自动变为贸易顺差。印度的出生率要比中国高很多，人口也要年轻很多。从life cycle理论的角度来看，就应该更多从外国借款搞建设，因此资本上应该是净输入，自动的经常项目下的逆差也很正常。当然如果经常项目下的赤字太大的话，首先不可能持久，第二外汇储备太低的话，更容易受国际金融市场波动影响，这两个方面需要平衡。印度现在还不到这个程度。尤其是我在网上查了一下，印度最近一段时间出口是增长，进口增长的更快，因此贸易逆差增大，但进口的很大一部分是印度人购买黄金大幅度增加，不是经济上有什么特别的结构性问题。

Dracula

五月 发表于 2017-9-6 19:17
这个说法是不对的。中国历年保持经常项目和资本项目的双顺差。下面是外汇管理局的数据：

单位：亿美 ...

你应该找本经济学教科书学习一下。

这是一个不错的英文的解释。中文的解释网上应该也能搜到。

Trade Deficit Is Really A Capital Surplus

http://www.independent.org/newsroom/article.asp?id=1832

The U.S. is on track for a record capital surplus! Sounds great, right? Now consider this: The U.S. is on track for a record trade deficit! It doesn’t sound so good, but the two mean pretty much the same thing. Whichever way you choose to say it, neither statement should be a cause for celebration or worry.

Newspapers around the country recently reported the Commerce Department’s new trade numbers. In July, the U.S. recorded a record $68 billion trade deficit, so we’re on track to surpass last year’s total trade deficit of nearly $717 billion.

News stories attributed the rising trade deficit to increased prices for foreign oil and other imports. But they neglected to ask fundamental questions about what a trade deficit really means and whether it is necessarily harmful.

The balance of payments accounting system has two major accounts: the current account and the capital account. The current account mainly measures trade in goods and services. The capital account mainly measures trade in assets. A trade deficit refers only to the current account balance.

Balance of payments accounting is done with a double-entry system of debits and credits. Each transaction involves both a debit and a credit.

Put simply, if you buy something from a foreigner, you must pay him—a debit is entered. Then the foreigner must somehow spend or save your payment—a credit is entered. When all credits and debits are added up, the entire accounting system must balance: The current account balance plus the capital account balance must sum to zero. Hence, a current account (trade) deficit implies a capital account surplus.

A trade deficit reflects the fact that we buy more goods and services from abroad than we sell to foreigners. Foreigners take the earnings they receive from our spending (minus the goods and services they buy from us) and invest that sum in the U.S. The U.S. has a wealth of investment opportunities, but we have a low rate of domestic saving, so lots of investments in the U.S. wouldn’t get funded if foreigners weren’t willing to supply us with their savings.

As long as our country remains a good place to invest and we have a low saving rate, foreigners are going to invest in the U.S. more on net than we invest overseas. That will generate a capital account surplus and the resulting trade deficit. This is a good thing.

When foreign investment increases our productive capacity, our economy can grow faster, enabling Americans to pay off any debts incurred. What about consumer debt? What if we borrow from foreigners to finance our consumption purchases? Is that part of the trade deficit bad? No. Every transaction summarized in the balance of payments is the result of individual transactions in which both parties to the exchange expected to benefit.

When a U.S. citizen finances a new car purchase, he does so because he values having the car now more than the amount he will have to pay back later. Does the outcome depend on whether he bought a Lincoln or a BMW? Buying a domestic Lincoln wouldn’t affect our trade deficit, but buying a foreign BMW would.

But whether the payment is to a foreigner or to a fellow citizen, the customer’s purchase still indicates that he deems himself better off from the transaction.

Sometimes the twin deficits—budget and trade—move in the same direction. When a government issues a lot of debt and there aren’t enough domestic savers to buy it up, a budget deficit will contribute to a trade deficit. That’s simply because the foreign purchase of bonds is recorded in the capital account.

After governments issue too much debt, they often harm their economy by inflating the money supply or raising tax rates to try to pay their debts. However, these problems stem from the budget deficit and the accumulated debt—not who finances the debt. In this way, a trade deficit can be a symptom of fiscal problems, but the trade deficit isn’t the problem per se. It’s the budget deficit that’s the problem.

Ultimately, most of the trade deficit results from voluntary market transactions, where both parties benefit from the sale of goods and assets. Adding up every transaction doesn’t suddenly eliminate the gains from trade just because U.S. citizens bought more goods and services than they sold.