为了防止银行恐慌的发生，我们首先需要知道它产生的原因：股市的崩溃、房地产泡沫的破裂（主要由银行信贷的快速膨胀引起）导致物价下跌、银行资产减值。存款人因资不抵债从银行取出存款，银行继而陷入了流动性危机。
银行的业务性质使其很容易受到流动性危机的影响。银行的主要盈利来源是短期存款和长期贷款，这通常被称作期限转换（或到期日的不匹配）。银行通过短期存款和长期贷款的利率差可以获得不菲收益。
如果没有期限转换，那么金融危机也将变得十分罕见。银行只需要借助短期存款来实现短期贷款义务，而不需要美联储提供额外的流动性。存在的唯一危机可能性就是借贷人的偿付能力。
银行在以下两个重要方面受到联邦政府的保护：
1、 联邦政府的存款保险保证了银行对存款人的偿付能力。
2、 银行可以从美联储的贴现窗口获得流动性。
纳税人充当了银行系统的缓冲器作用：纳税人为银行的坏账买单，为银行提供了额外的流动性。银行体系的崩溃必然会拖垮整个经济体。纳税人能做的是阻止银行去冒偿付能力或流动性风险
偿付能力风险
纵观历史你会发现，为了解决特定问题采取的措施日后往往会造成刚大的问题。1907年的金融恐慌使美联储于1913年应运而生。美联储为银行提供了安全保证：法定准备金的下降、公开市场买卖、压低贷款利率，使得银行快速的扩展信贷业务，最终导致了1929年的经济危机。
防止银行面临清偿能力风险的第一步就是防范资产泡沫的发生。限制美联储对市场利率的干预可以使市场的信贷实现自然平衡。信贷规模的扩张会导致还款利息的上涨，进一步的借贷规模便会减小。
第二步就是逐渐提高银行的法定准备金。最直接的方法是迫使银行提高产权资本，另外一个比较受欢迎的方法是格雷戈里•曼昆提出的，如果金融监管机构认为银行资金不足，便可要求银行增加可转化为资金的或有债务。
第三步是沃尔克法则：限制银行利用自身资本进行自营交易。允许银行交易高达其资金的3%的规定让我很不满意，因为法规越明确就越难以实施。不久之后，银行就会利用杠杆进行大规模交易，而且，这也给比例（3%）幅度增加敞开了大门。
流动性风险
正如之前所说的，流动性风险产生的主要原因是到期日的不匹配性。根据美联储的零利率政策，银行可以付给通知存款者接近于零的利率，银行可以用存款者的资金借贷或投资，这就为银行创造了很大的利润空间。这么做会使银行过度依赖于短期存款，是不值得提倡的。
如果投资机构1的短期存款平均为两周，该机构将短期存款的资金用于平均为六年的投资；同样水平的投资机构2的短期存款平均为两周，进行回报周期为两周的短期投资；机构3的存款周期为12个月，进行为期6年的投资。那么机构1相对于机构2、3会面临更大的流通性风险。
最简单的方法是提高上述机构（依赖于短期存款）的法定准备金，这也会降低其在繁荣时期的信贷扩张速度。
存款保险
当一个了不起的主意变成一个坏主意。
存款保险在20世纪30年代被引入并挽回了美国银行濒临灭绝的境地。由联邦存款保险公司对各大银行征收存款保险。然而，这后来引发了道德危机。在联邦存款保险公司的担保下，存款者不必担心银行的清偿能力。高风险的机构可以和那些经营良好、低风险的机构在同等的条件下竞争。这无疑导致了更高的坏账率，比如20世纪80年代的储蓄和贷款危机。
联邦存款保险公司在监管存款机构方面做得很好，但是却不可以取代市场的作用。存款保险在经济危机的时候起到了十分关键的作用，但是当危机结束之后，应该减少它的幅度，比如将最高保险金额设为两万美金或者赔付被保金额的90%。这就足以让存款者谨慎选择存款机构，并增加经营良好的存款机构的竞争力。
影子银行
不受监管的影子银行曾两次威胁到整个金融体系：1907年不受监管的投资信托基金和2007年的投资银行。银行法规和法定准备金的要求应该适用于所有涉及期限转换的机构。
证券化
不动产证券化的盛行是引起1929年金融危机的首要因素，并且导致了最近的这次金融危机。证券化掩盖了期限转换的本质:长期资产来源于流动性的市场融资，并可以短线交易（类似于股票）。其中的问题存在于，在经济危机市场缺少流动性的时候，就只剩下短线投资者和长期资产。上个世纪末，受监管的银行为了规避准备金大规模施行不动产的证券化。抵押贷款证券化加剧了金融危机。
房利美和房地美
房利美成立于1938年，经济大萧条结束之际，促进了房地产市场的发展。1968年私有化，并在1970年收购了房地美—-为了提升其在房地产市场上的竞争力。因受到政府的支持，房利美和房地美发展迅速，在2008年拥有或担保约半数12美元万亿美元的住宅抵押贷款市场。房地产泡沫破裂之后，房利美和房地美被联邦住房金融局的接管。为了增加国库资金，国家债务限额提高到了8000亿美元，其中美联储购买了12.5亿美金的证券以支持按揭市场，降低抵押贷款利率。
房利美和房地美迄今已花费美国纳税人$1450亿的救市成本，将继续对金融市场的稳定和纳税人的钱包构成威胁。唯一的长期解决方案就是让它破产，并拍卖它的资产。
结论
你不能有效地规范了银行业，同时允许大部分金融业的绕过银行法规。唯一的办法就是对证券和其他大规模涉及期限转换的机构施行同样的法规和准备金要求，从而创造一个公平竞争的环境。同样重要的是，要通过提高准备金要求来防止银行在纳税人资金的庇护下进行自营交易。
Preventing Future Banking Panics
To protect ourselves from future banking panics we need to understand the underlying causes. Panics are normally precipitated by an insolvency crisis, which then escalates into a liquidity crisis as depositors rush to withdraw their funds. The most common cause of a solvency crisis is the collapse of a stock market or property bubble, with a sharp fall in prices leaving banks exposed to write-downs. And the primary cause of asset bubbles is a rapid expansion in credit leading to inflation of asset values.
Banks are also particularly vulnerable to liquidity crises because of the nature of their business. Their major source of profits is from borrowing short and lending long, commonly referred to as maturity transformation (or maturity mis-match), where they make a healthy margin between long-term loan rates and short-term deposit rates.
Without maturity transformation, systemic banking panics would be extremely rare. Banks would call in short-term assets to meet their short-term obligations, with no need for the Federal Reserve to provide additional liquidity. The only remaining crises would be solvency-based.
Banks are protected by the federal government in two important ways:
1. Solvency is guaranteed by deposit insurance where the federal government underwrites bank liabilities to depositors; and
2. Liquidity is provided by the Federal Reserve discount window where banks can obtain additional liquidity in the event of a run.
The taxpayer effectively acts as a buffer to the banking system, absorbing losses which the banks cannot withstand, and providing additional liquidity as required. There is no way around this as collapse of the entire banking system would bring down the entire economy. What the taxpayer can do, however, is to discourage banks from taking unnecessary solvency or liquidity risks.
Solvency Risks
If we examine history we will find that measures introduced to solve a particular problem often end up causing far greater problems in the long run. The creation of the Federal Reserve in 1913, in response to the banking panic of 1907, provided a safety net for banks. The safety net enabled banks to take on more risk, with capital reserves levels falling sharply. And open market operations by the Fed enabled the rapid expansion of credit prior to the 1929 crash.
So the unintended consequence of measures taken to protect against future banking panics was to almost halve capital reserve ratios and facilitate the rapid expansion of bank credit through suppression of market interest rates.
The first step in protecting banks against solvency risk is to guard against future asset bubbles. Limiting Fed interference with market interest rates would provide a natural counter-balance to credit expansion. Expansion would cause interest rates to rise, thereby deterring further borrowing.
The second step is to gradually increase bank reserves. The direct route would be to force banks to raise additional equity capital. An appealing alternative proposed by Gregory Mankiw is to require banks to raise contingent debt that can be converted to equity if the financial regulator deems the bank to have insufficient capital.
The third step is the Volcker rule: to prevent banks from engaging in proprietary trading while enjoying the protection of the taxpayer's dollar. I am uncomfortable with the 3 percent rule, which allows banks to trade up to 3 percent of their capital. Rules are far easier to enforce when they are absolute. How long will it take the banks to find a way to leverage the 3 percent into a significant exposure? It also leaves the door open for later increases in the percentage limit.
Liquidity Risk
The primary cause of liquidity risk, as discussed earlier, is maturity mis-match. With the Fed's zero interest rate policy, banks pay close to zero interest on call deposits, netting them a handsome spread when they lend/invest that money in the market at longer maturity. This can lead to over-reliance on short-term funding and should be discouraged.
An institution that raises deposits with an average maturity of 2 weeks and invests these in loans with an average maturity of 6 years has far greater liquidity risk than an otherwise identical institution that invests in short-term financial assets with an average maturity of 2 weeks — or an institution that raises deposits with an average maturity of 12 months and invest in identical loans with a maturity of 6 years.
The easiest solution may be to increase capital reserve requirements for institutions who engage in short-term funding. That would also slow the rate of credit expansion during a boom.
Deposit Insurance
When too much of a good idea becomes a bad idea.
Deposit insurance was introduced in the 1930s and saved the US banking system from extinction. Administered by the FDIC, and funded by a levy on all banking institutions, deposit insurance, however, encourages moral hazard. Depositors need not concern themselves with the solvency of the bank where they deposit their funds so long as deposits are FDIC insured. High-risk institutions are able to compete for deposits on an equal footing with well-run, low-risk competitors. This inevitably leads to higher failure rates, as in the Savings & Loan crisis of the 1980s.
The FDIC does a good job of policing deposit-takers, but no regulator can substitute for market forces. Deposit insurance is critical during times of crisis, but should be scaled back when the crisis has passed. Either limit insured deposits to say $20,000 or only insure deposits to say 90% of value, where the depositor takes the first loss of 10%. That should be sufficient to keep depositors mindful as to where they bank. And restore the competitive advantage to well-run institutions.
Shadow Banking
Development of an unregulated shadow banking system has twice come close to bringing down the entire financial system: unregulated investment trusts in 1907 and investment banks in 2007. Banking regulations and capital reserve requirements should apply to all institutions who engage in large scale maturity transformation.
Securitization
Securitization of real estate assets was rife in the lead up to the crash of 1929 and again in the lead up to the latest financial crisis. Securitization often masks maturity transformation, where long-term assets are financed through liquid markets and traded on a short-term basis in much the same way as stocks. The problem is that liquidity tends to dry up during a crisis, leaving short-term investors with a long-term asset. Banks engaged in massive securitization in the last decade in order to circumvent capital reserve requirements. This exacerbated the financial crisis when the market for mortgage-backed securities (MBS) dissolved.
Fannie Mae and Freddie Mac
Fannie Mae was founded in 1938, towards the end of the Great Depression, to facilitate mortgage finance for home buyers and to stimulate the real estate market. Privatized in 1968, it was joined by Freddie Mac in 1970 — to foster increased competition in the home mortgage market. With an implicit government guarantee, the two thrived and by 2008 owned or guaranteed about half of the $12 trillion US residential mortgage market. Following the collapse of the real estate market both were placed under the conservatorship of the FHFA. The national debt ceiling had to be increased by $800 billion to allow for increased Treasury funding, while the Fed purchased $1.25 billion of mortgage-backed securities to support the MBS market and reduce mortgage rates.
Fannie Mae and Freddie Mac have so far cost US taxpayers $145bn in bail-out costs and will continue to pose a threat to the taxpayer purse and stability of financial markets. The only long-term solution is to break them up and sell them off — with the clear understanding that there will be no implicit federal guarantee.
Conclusion
The bottom line is that you cannot effectively regulate the banking industry while allowing large parts of the financial sector to bypass banking regulations. The only solution is to create a level playing field by imposing the same regulations and capital reserve requirements on the securitization industry and any other institution that engages in large scale maturity transformation. It is also vitally important that we control the expansion of credit, in part by increasing capital reserve requirements, and prevent banks from engaging in proprietary trading while under taxpayers protection.
I have not discussed bank's use of derivatives and when too-big-to-fail extends to non-banking entities, in the insurance sector or in general industry. These will be covered in a later paper.
本文翻译由兄弟财经提供，
文章来源：http://www.incrediblecharts.com/economy/banking_panics.php