美国金融危机的原因及启示
当前美国因次贷问题而引发的华尔街金融危机成了全世界关注的焦点。发生在华尔街的金融危机不仅重创了美国脆弱的经济，引起美国股市崩盘，也给出其它国家经济带来极大危害。那么为什么华尔街会发生严重的金融危机? 这场金融危机带给我们什么启示？本文拟对此进行探讨。
一、美国金融危机的原因
美国因次贷问题而引发的金融危机有着复杂的确背景，我认为其主要的原因有以下几点：
1.刺激经济的超宽松环境埋下了隐患
2007年4月2日，美国第二大次级贷款机构新世纪金融公司宣布破产，标志美国次贷危机大爆发。次级抵押贷款危机的源头是其前期宽松的货币政策。在新经济泡沫破裂和“9.11”事件后，为避免经济衰退，刺激经济发展，美国政府采取压低银行利率的措施鼓励投资和消费。从2000年到2004年，美联储连续降息，联邦基金利率从6.5%一路降到1%，贷款买房又无需担保、无需首付，且房价一路盘升，房地产市场日益活跃，这也成就了格林斯潘时代晚期的经济繁荣。提供次级抵押贷款本是一件好事，使得低收入者有了自己的住房。对一般个人家庭来说，低利率和房产价格一路飙升，编织出一幅美好的前景，投资住房成为巨大的诱惑，于是大量居民进入房贷市场。到2006年末，次贷涉及到了500万个美国家庭，目前已知的次贷规模达到1.1万亿至1.2万亿美元。
2.以房产作抵押是造成风险的关键
美国次贷的消费者以房产作抵押，房产的价格决定了抵押品的价值。如果房价一直攀升，抵押品价格保持增值，不会影响到消费者的信誉和还贷能力。一旦房价下跌，抵押品贬值，同一套房子能从银行贷出的钱就减少。如果贷款利率被提高，次贷使浮动利率也随着上升，需要偿还的钱大大增加。次贷贷款人本来就是低收入者，还不上贷款，只好放弃房产权。贷款机构收不回贷款，只能收回贷款人的房产，可收回的房产不仅卖不掉，还不断贬值缩水，于是出现亏损，甚至资金都流转不起来了。房价缩水和利率上升是次级抵押贷款的杀手锏。
从2005年到2006年，为防止市场消费过热，美联储先后加息17次，利率从1%提高到5.25%，市场利率进入上升周期。由于利率传导到市场往往滞后一些，2006年美国次贷仍有上升。但加息效应逐渐显现，房地产泡沫开始破灭。
3.次级贷款资产的证券化加重了危机的扩散
美国绝大多数住房抵押贷款的发放者是地区性的储蓄银行和储蓄贷款协会，地方性的商业银行也涉足按揭贷款。这些机构的资金实力并不十分雄厚，大量的资金被投放在住房抵押贷款上对其资金周转构成严重的压力。一些具有“金融创新”工具的金融机构，便将这些信贷资产打包并以此为担保，用于发行可流通的债券。给出相当诱人的固定收益，再卖出去。许多银行和资产管理公司、对冲基金、保险公司、养老基金等金融机构投资于这些债券。抵押贷款企业有了源源不断的融资渠道，制造出快速增长的新的次贷；投资机构获得较高的收益。
各种各样的金融衍生工具使得投资机构现金流得到更合理的利用，利益也得到了分解和共享，风险也得到了分摊。但事物都有两方面，金融创新制度带来风险分散机制的同时，也会产生风险放大效应。像次贷这样一种创新使美国不够住房抵押贷款标准的居民买到了房子，同时通过资产证券化变成次级债，将高风险加载在高回报中，发散到了全世界。从这个意义上说，凡是买了美国次级债的国家，就要被迫为美国的次级危机“买单”。当房地产泡沫破裂、次级贷款人还不起贷时，不仅抵押贷款企业陷入亏损困境，无力向那些购买次级债的金融机构支付固定回报，而且那些买了次级衍生品的投资者，也因债券市场价格下跌，失去了高额回报，同样调进了流动性短缺和亏损的困境。自2007年第三季度开始，金融机构开始报告大额损失，反映了抵押贷款和其他资产的价值大幅下跌。
次级贷款资产的证券化过程实际上是资产组合和信用增级的一个过程，也是多种资产叠加、多个信用主体信用叠加的一个过程，在资产证券化后，这种资产证券化组合的信息和相关风险信息披露可能趋于更加不透明，导致市场中很少有人能清楚地读懂其中的风险，更不用说对其进行实时的风险定价了。由于对资产真正的价值和风险认知不足，投资者严重依赖评级公司的报告作出决策。信用评级机构的信用评级在金融市场的作用和影响已经越来越大，信用评级也是资产证券化过程中的必要和重要环节。信用评级是否客观公正，是否真正了解金融工具，是否存在着利益冲突和道德风险等，这些因素都会对全球金融市场产生重大影响。次级抵押贷款债券本来是从一些低质资产发展而来，“金融创新”则使这些低质资产通过信用评级公司评级获得了高等级标号，事后证明价值被严重高估。
由于信息不对称和风险损失不明，一旦次级抵押贷款出现了重大风险和损失，构筑在这些证券上信用增强和信用叠加也会如同沙漠上的空中楼阁一般会“瞬间倒塌”，由此必然会引起广大投资者的投资信心恐慌，规避风险的本能加速了投资者的抛售，并加剧了金融市场的动荡，金融灾难也就在劫难逃。在次贷、证券化、信用衍生产品这个风险传递链条中，如果没有信用评级公司的参与，次按危机或许根本就不能发生。
二、美国金融危机的启示
美国因次贷问题而引发的金融危机给我们的教训是深刻的，我国应引以为诫。
1.认识和防范房贷的市场风险
房贷有房产作抵押，似乎是最安全的资产，但房产的价值是随着市场不断变化的。当市场向好时，房地产价格上扬会提高抵押物的市值，降低抵押信贷的风险，会诱使银行不断地扩大抵押信贷的规模。但房地产的价格也不可能无休止地涨下去，因为任何企业或个人都不可能无视其生产与生存的成本。当市场发生逆转时，房价走低，银行处置抵押物难，即使拍卖抵押物，其所得收益也不足以偿还贷款。这不仅给贷款银行带来大量的呆账坏账，还会危及银行体系的安全及整个经济的健康发展。因此，银行需要在风险和收益中做出理性的选择，提高识别和抵御市场风险的能力。
2.认识和防范信用风险
次级贷款违约率高，原因在于贷款机构在放贷中没有坚持“三C”的原则，即对借款人基本特征（Character）、还贷能力（capability）和抵押物（collateral）进行风险评估。从国外的经验看，借款人的基本特征（年龄、受教育水平、健康状况、职业）、购房目的（自住还是投资）、婚姻家庭状况，还贷能力（房贷房产价值比、房款月供收入比、家庭总债务收比、资产负债比等）和抵押物（房产价值、新建房、二手房、使用期限、地段、独户、多层高层建筑等）都与违约率密切相关。
香港在东亚危机中资产价格大幅缩水，许多购房者承受负资产的压力，但银行却没有出现违约率大幅上升的问题，就是因为香港银行业自身有较强的抗风险能力，对个人住房贷款有严格资格审查标准，借款人购房多是自住，职业稳定，收入现金流不变，房产使用价值不变，仍会按期还贷。
我国的商业银行在扩大个贷业务中应避免“政绩目标”等非经济和非理性色彩，减少行政手段介入信贷资金配置，加强对借款人还贷能力的审查，对不同信用风险等级的借款人实施不同的风险定价、借贷标准，包括自有资本金、首付比例、利率、期限等，以促进银行从服务风险定价向客户风险定价转变，从粗放经营向精细化、个性化转变，提高自身抵御风险的能力。
3.建立完善信息披露机制和贷款规范
监管部门应监督从事住房信贷的银行和保险机构，在各类贷款和保险产品的营销中，要向借款人充分披露产品信息，让借款者有充分的知情权、选择权，减少信息不对称对借款人权益的损害。推进标准化的合约、贷款审核程序、借贷标准，规范银行贷款行为和贷后的服务。
4.建立房地产金融预警和监控体系，提高抗风险能力
既然金融风险在经济生活中无处不在，是一种不以人的意志为转移的客观存在，监管部门的职责就是提高风险识别的能力，预测、防范、规避和化解风险，提高风险的可控性。因此，建立房地产金融预警和监控体系是迫在眉睫，它将对银行体系的安全，房地产市场和整个国民经济持续健康发展产生积极促进作用。
5.政府部门应从危机中得到警示
让百姓安居乐业是政府的职责，但“人人享有适当住宅”并不意味人人都要买房，让无支付能力的低收入者进入购房市场，拔苗助长不仅事与愿违，还会产生许多负效应。特别在我国抵押担保、抵押保险等相关金融基础设施不健全的情况下，无形中让银行承担了许多政策风险。因此，一个优化的住宅市场结构应是新建房与存量房，出售房与租赁房，商品房与政府提供公共住房多样化的统一。政府应加大经济适用房的供给，改变经济适用房“只售不租”为“租售并举”；并通过信贷、税收、土地政策引导房地产企业增加中低价位普通商品房的供给，在开工许可审批中优先考虑普通商品住宅。
6.中国应建立健全抵押保险和担保制度
中国应建立健全抵押保险和担保制度，完善住房信贷风险防范和分担机制。引入商业保险和政策性担保的机制，有利于促进抵押贷款营销的规范化、合约的标准化，抑制商业银行盲目放贷的冲动;合理的保险风险定价机制，有助于商业银行规避信用风险、道德风险和房地产市场周期波动风险。
仅供参考，请自借鉴。
希望对您有帮助。

The term financial crisis is applied broadly to a variety of situations in which some financial institutions or assets suddenly lose a large part of their value. In the 19th and early 20th centuries, many financial crises were associated with banking panics, and many recessions coincided with these panics. Other situations that are often called financial crises include stock market crashes and the bursting of other financial bubbles, currency crises, and sovereign defaults.
Many economists have offered theories about how financial crises develop and how they could be prevented. There is little consensus, however, and financial crises are still a regular occurrence around the world.
The global financial crisis of 2008 is a major financial crisis, the worst of its kind since 1987, and which is ongoing as of mid-November 2008. It became prominently visible in September 2008 with the failure, merger or conservatorship of several large United States-based financial firms. The underlying causes leading to the crisis had been reported in business journals for many months before September, with commentary about the financial stability of leading U.S. and European investment banks, insurance firms and mortgage banks consequent to the subprime mortgage crisis.
Beginning with failures of large financial institutions in the United States, it rapidly evolved into a global crisis resulting in a number of European bank failures and declines in various stock indexes, and large reductions in the market value of equities (stock) and commodities worldwide. The crisis has led to a liquidity problem and the de-leveraging of financial institutions especially in the United States and Europe, which further accelerated the liquidity crisis. World political leaders and national ministers of finance and central bank directors have coordinated their efforts to reduce fears but the crisis is ongoing and continues to change, evolving at the close of October into a currency crisis with investors transferring vast capital resources into stronger currencies such as the yen, the dollar and the Swiss franc, leading many emergent economies to seek aid from the International Monetary Fund. The crisis was triggered by the subprime mortgage crisis and is an acute phase of the financial crisis of 2007–2008.

The global economic summit
After the fall
Nov 13th 2008
From The Economist print edition
On November 15th world leaders are due to sit around a table in Washington, DC, to fix finance. They have their work cut out
Illustration by Bill Butcher
THE leaders arriving in Washington, DC, for this weekend’s economic summit are being presumptuous. If they want what they are calling Bretton Woods 2 to live up to the original, which took place in New Hampshire overshadowed by war and the Depression, it will have to establish a new economic order for the capitalist world. In 1944 that meant creating the IMF, the World Bank and a body to oversee world trade. Imagine Hank Paulson, America’s treasury secretary, as John Maynard Keynes; or picture Gordon Brown, Britain’s prime minister, as Winston Churchill (as Mr Brown himself secretly may), and you get a sense of the task ahead.
The Bretton Woodsmen of 2008 are grabbing the credit before they have earned it—rather as all those subprime householders did. More than two years of gruelling technical work laid the ground for the wartime conference of officials and finance ministers (prime ministers and presidents had other things to deal with). By contrast, the leaders gathering this weekend from the G20, a mix of industrial and emerging countries, plus the European Union, have cobbled together an agenda in a few frenetic weeks. They will doubtless produce no shortage of promises. Just what these are worth will depend on sweat and summits yet to come.
The summit is sure to stir up a debate about the institutions that oversee the international economy. By convening the G20 rather than the closed, rich club of the G7, the old order has in effect acknowledged that the rest of the world has become too important to bar from the room. But what new order should take its place? Answering that question has been a parlour game for economists since long before the crisis. By encouraging them to dust off their pet ideas, the summit will at the very least create a bull market in new schemes for global economic governance.
Because everyone agrees that something big needs fixing and that the world expects action, calling the summit Bretton Woods 2 could yet come to be seen as a rallying cry for reform. And yet there are lots of reasons to see it as vainglory. The agenda is vague and sprawling. With so many of the world's political leaders sitting around the table, it will be hard to escape platitudes and hypocrisy. There may be disagreements—especially where sovereignty or competitiveness is threatened. And most of all, the recent international financial collaboration is fraught with in-fighting and complexity.
At first sight, this summit seems no different. For instance, consider how Mr Brown and Nicolas Sarkozy, the president of France, have vied to claim paternity of the summit for their own domestic reasons. Mr Sarkozy sees a chance to show he is a man of action, and he will find it easier to force through domestic reform if he can show he is not in thrall to all that Anglo-Saxon free-market ideology.
Mr Brown has been calling for a global summit for weeks, emboldened by international acclaim for his plan to rescue Britain’s banking system. The prime minister is keen to show that the crisis is one of those worldwide messes that—honestly—has nothing to do with the past 11 years of Labour government. And he wants to play the lead in Washington so as to protect the free-market City of London from the Gallic machinations of Mr Sarkozy.
From despair, hope
But there is more to the summit than politics. Perhaps inevitably, the run-up to the summit has produced dozens of different proposals. Broadly, they fall into three areas. First and most urgent is the need to limit the crisis, which is even now spiralling from the rich world to emerging economies. Second is financial regulation: its flaws have been laid bare, and the summiteers will want to put it right. Third is global macroeconomics. The G20 needs to find ways to correct the imbalances—Asian saving and Western spending—that lay behind the boom.
Pervasive economic gloom is the best reason for hoping that something important will come of this weekend’s meeting. After savaging the financial markets, the credit crisis has broken loose into the real economy. This month the IMF lowered its forecast for global growth next year by 0.8 percentage points, to 2.2%. The rich world is already in recession. Unemployment, foreclosures and corporate bankruptcies are rising. Emerging economies have also been ensnared, as investors from richer countries retreat to their home markets. The fund cut its forecast for their growth rate by a percentage point, to 5.1%.
Such pain demands an ambitious policy response. On November 6th Kevin Warsh, a governor of the Federal Reserve, put it in dramatic terms: “We are witnessing a fundamental reassessment of the value of every asset everywhere in the world,” he said. “The establishment of a new financial architecture, thus, is the essential policy response to the greatest economic challenge of our time.”
The easy bit will be to harness that sense of urgency to produce concerted interest-rate cuts and government spending. Already, several countries are talking about a co-ordinated fiscal stimulus to help offset a collapse of private-sector demand. China set the standard on November 9th, with a huge spending plan worth 4 trillion yuan (nearly $600 billion), or about 15% of GDP (see article). Not everyone can muster such resources, but other countries, including America and Britain, are preparing to act too. Germany, which has promised a piffling €12 billion ($15 billion), may be shamed into spending more. With concerted action, countries will find that each national stimulus buys more confidence than it would do alone.
Many commentators also want to build confidence by increasing the spending power of the IMF. If a large emerging market, such as Poland or Turkey, were to need help, says Willem Buiter, an economist at the London School of Economics, its present resources of $250 billion “would be gone before you can say ‘special drawing rights’.” Although some European delegates want to strengthen the IMF, the Americans are resisting: the summit may produce nothing more than a pledge to find the money if the fund needs it.
In financial regulation, some changes ought to be easy to agree on—such as ensuring that banks stop holding assets off their balance-sheets and put capital aside against possible failures in a wider range of securities. The summit is also likely to try to bring order to the market for credit-default swaps, which trade the risk that borrowers will not honour bonds, by concluding that, within 120 days, the business should be routed through clearing houses rather than settled privately by investors.
That is progress, to be sure. But it is small potatoes next to the summiteers’ ambitions. And little else will be easy, even if the leaders can issue a declaration that sets out their common principles and a schedule of negotiations for further reform. To see why, leave behind the first Bretton Woods conference for the more recent history of international financial regulation.
No end of squabbles
Illustration by Bill Butcher
The difficulty with cross-border rules in finance is explained by Barry Eichengreen, a professor at the University of California, Berkeley, and one of 20 economists from around the world who have written an “e-book”* that describes what this weekend’s summit should do.
On the one hand, finance is every country’s business. This crisis has shown that what happens deep inside one national financial system can wreck another halfway across the world. In the United States subprime lending was a relatively small bit of the mortgage market—itself just a part of America’s financial markets. And yet the cascade of failing credit and risk aversion that began there, partly as a result of inadequate supervision, has spread not just to the overstretched banking systems of Europe, but also now to untroubled banks in emerging markets.
On the other hand, nation-states jealously guard the right to oversee their own banks. This is not just out of principle, or a desire to see that the regulations suit their own financial institutions—although most regulators would think these alone to be sufficient reason. It is also because, when a crisis comes, the nation-state foots the bill for a bail-out. In addition, Wendy Dobson, of the University of Toronto, notes that regulators need intimate local knowledge of their charges and their own financial structures if they are to have a hope of prevailing—and even then, as the world has seen, the odds are against them.
The tug between national and supranational regulation has gradually led to an ad hoc arrangement for the international banking system. In the 1980s America and Britain grew worried about the expansion of Japanese banks, which by 1988 accounted for nine of the world’s ten largest by assets, up from one at the start of the decade. What bothered the West was that Japanese regulators allowed their banks to count shareholdings as core capital. Cheap capital fed their growth. And it was indeed reckless, as the subsequent collapse of the Japanese stockmarket showed.
Under the auspices of the Bank for International Settlements (BIS), a central bankers’ central bank in Basel, in Switzerland, the big economies agreed to set common standards for what counted as capital and how much a bank should hold in order to qualify as safe. Their negotiations were partly about rules to make the global financial system more resilient. But they were also, in effect, about a trade dispute, over what the West saw as a subsidy to Japan’s banks. This ambiguity between the common good and national interests complicates all financial negotiations—including any that will follow the G20 summit.
Andrew Gracie, who worked on regulatory design at the Bank of England and founded Crisis Management Analytics, which advises central banks on financial stability, points out that right from the start regulators looked at systemic risk one bank at a time. The assumption was that if each institution was safe, then the system as a whole would be too. Similarly, when banks had many subsidiaries, regulators short of money and time tended to worry only about their own piece of the jigsaw.
This “micro-prudential” philosophy was always questionable. Now it looks absurd. Banks tend to own similar assets. In a crisis the capital of the entire industry tends to fall, which means that the instability of one bank can undermine the standing of the next. Hence the talk about a new “macro-prudential” sort of regulation that seeks to take account of the whole system’s vulnerabilities, as well as the health of individual banks, by, say, adjusting capital charges over the economic cycle.
The strengths of the original Basel standards (Basel 1) lay in being reasonably simple to negotiate and administer. But therein lay their weaknesses also. Banks soon started to favour business that was profitable (ie, risky) but which, under Basel 1’s crude definitions, escaped the appropriate capital charges. As the banks adapted to Basel 1, so the rules became less useful.
That gave rise to the effort to create Basel 2, which began in the late 1990s. This sought to strike a different balance, by asking banks to be more sophisticated in assessing the riskiness of their assets and thus their capital requirements. But sophistication came at a high cost. A recent book† by Daniel Tarullo, a professor of law at Georgetown University who is fancied for a senior economic post under Barack Obama, describes how the negotiations dragged on for years as governments jostled for a deal that would give their own banks some advantage. Mr Tarullo observes that the banks would accept all sorts of arbitrary provisions as long as the end result was to reduce the amount of capital they had to put aside.
Faults and lessons
Basel 2 is a flawed agreement. Although it is not yet in force, it already needs updating. Its chief failing is its reliance on rating agencies and the banks’ own models of the risks that they are carrying—an idea that has been discredited by the way banks have been caught out. In addition, the accord did not allow for the evaporation of liquidity that prevented the banks from financing their businesses. It is hardly reassuring that the minimum capital that rescued banks are aiming for today is far above the minimum set by Basel 2.
The story of bank-capital standards contains important lessons for the leaders gathering at the G20. The talks dragged on because their objectives were unclear, the subject matter was complex, negotiators were fighting for the upper hand and there was little sense of urgency. Even if all that can be put right, the schedule of work has expanded. Supervision may need to extend beyond banks, to any financial institution whose failure could threaten financial stability, which might include some large hedge funds and non-bank financial companies such as GE. The capital-standards regime also needs to become more macro-prudential. Regulators need to be able to put more trust in banks’ risk models and rating agencies and supplement them with simple rules about the level of borrowing. Mr Tarullo suggests that banks should issue new securities to serve as gauges of investors’ faith in them.
There are two difficulties in all this. The first is that it will take time and, as urgency fades and the negotiators drown in complexity, national interest may gain at the expense of collective safety. The second is that original dilemma: international rules require enforcement, but nation-states demand sovereignty. Dominique Strauss-Kahn, head of the IMF, wants an inspectorate. Mr Eichengreen has proposed a World Financial Organisation, with disciplinary panels. The EU wants “colleges” of national regulators for each bank and an IMF to give warning of crises. The summit looks most likely to back the EU idea—but it ought to be more ambitious. The system will work only if governments heed outside warnings. But just look at how they browbeat the IMF into giving favourable assessments of their economies.
Although this summit looks likely to dwell on financial regulation, it cannot ignore the macroeconomics that preoccupied the original Bretton Woods conference all those years ago. As Martin Wolf, a columnist at the Financial Times, explains in a new book‡, the boom was fuelled by the imbalances that grew out of the Asian financial crisis in 1997.
Illustration by Bill Butcher
Countries that had grown used to incoming foreign capital suffered terribly when it suddenly flowed back out again. To protect themselves in future, they started to run current-account surpluses and to amass foreign-exchange reserves. Spendthrift America and Britain were happy to help Asia save, even if that meant running the corresponding deficits.
Surpluses are all very well, but they cannot continue to accumulate for ever. Perversely, if they unwind violently, they will create instability. Much of the cheap money recycled from the saving countries found its way into housing and other assets in the West. It was too much to hope that it would flow back out of those assets in an orderly way.
The conflict between sovereignty and safety here is even less easy to disentangle than it is in financial regulation. Clearly, no country would agree to live by a rule that it should balance its current account. Raghuram Rajan, a professor at the University of Chicago and a former chief economist at the IMF, points out that current-account surpluses and deficits can indeed help countries cope with shocks and finance investment. At the same time, no international organisation like the IMF could plausibly have the independence or the resources to make a credible promise to back all the economies suffering from capital flight in a crisis.
This conundrum leads straight back to a souped-up IMF—still too small to save the world, admittedly, but bigger than today’s, and backed by swap lines from the three large regional central banks, the Fed, the European Central Bank and eventually the People’s Bank of China. For that to work and for the IMF’s help to lose some of its stigma, rich countries will have to admit more emerging economies to the fund’s board. Cue yet more difficult negotiations.
There are two ways of thinking about this weekend’s summit in Washington. To be charitable, look on and wonder at the sheer ambition of taking on so many hard, important questions. A severe financial crisis may be the only time when the technicalities wallowing near the bottom of policymakers’ agendas receive the attention they deserve. But there is a more cynical interpretation. Perhaps the summiteers will bask in the headlines and then, out of the glare of the television lights, set about something disappointingly modest.
我摘选了其中一篇.在economist上的网站上有许多,在http://www.economist.com/,搜索economic crisis